This all started a couple of weeks ago, when I should have been studying for final exams. Instead, I was procrastinating by flipping through Zenith Nadir's excellent collection of toolkits, Z-Files, romanticizing about the days of toolkits.
At some point, I wondered which toolkit was the most popular. Then I thought, hey, I could probably write a toolkit-counting program!
And so I wasted the last couple of weeks writing toolkit-counting programs and staring at toolkits for hours on end. The first two programs sucked. The latest version still sucks: it's slow, and it isn't completely automated. But it works, and I'm tired of staring at toolkits.

When a toolkit is included in a world multiple times, it only counts once. For multi-board toolkits (e.g., STK), I only counted the most popular board; this is so 2-board toolkits don't appear twice as popular as 1-board toolkits. Object libraries and ASCII charts are not included.
Authors delete toolkits to save space. Authors change toolkits, both accidentally and intentionally. I might have missed a toolkit. I made all sorts of sloppy categorization decisions. The above results are incorrect for a million reasons, but they are a good enough indicator of toolkit popularity, in my opinion.
Blah blah blah blah blah. Pretty pictures!
STK: 13.89% (596/4291)

The most popular toolkits are the earliest. STK is a horrible toolkit, because you have to import a bunch of boards to do anything fancy graphically. Almost all the other toolkits fit much more stuff in much less space. But STK was first, and so it got the most use.
The Objects board is the most popular (596), followed by Fake Walls (504), Normal Walls (413), and Doors, Passages, and More (408). Items and other basic terrains are also pretty popular. Nothing too surprising.
Shades Toolbox: 9.35% (401/4291)

If you leave empty space on your toolkit, someone will eventually fill it with something. Seems like this was one of the more modified boards. It's also one of the most copied -- a bunch of toolkits use that color layout.
ZOP's Mega Color Toolbox: 6.29% (270/4291)

As usual, the really popular toolkits tend to be the older ones, simply because they got there first. The second version came out in 1998, but the 1996 version got the most use. Again, users added on all sorts of junk.
Draco Toolkit: 4.73% (203/4291)

First toolkit so far that really packs a bunch of stuff on one board. Early versions of this toolkit only got a few uses, but for some reason, 5.0 and 6.9x really took off: 49 worlds with 5.0 and 134 with 6.9x. Not sure why.
SNACK: 4.33% (186/4291)


As with the Draco Toolkit, later versions of SNACK were more popular. However, the popularity of SNACK was a bit more spread out, in that almost all the versions saw some use. It looks like most people who used SNACK 4.0 included both boards, though several dropped the second one.
Lemmer Toolkit: 3.40% (146/4291)

I didn't count the abbloipp toolkit here, because that toolkit has a radically different structure from the rest of this line of toolkits. That's an ad-hoc categorization decision on my part -- if you disagree with it, just add 18 to the count. abbloipp aside, vBlegh and v100 (a revision of vBlegh) account for almost all of the Lemmer Toolkits.
vstk: 3.26% (140/4291)

The most popular versions here are vbeegees - se and v. peter gabriel, both pretty late versions of this toolkit. The earlier versions still saw some use, though. Also, is there a reason why people put horizon fades on the right side of the board?
Nomo7: 2.91% (125/4291)

Again, I decided not to include a radically different version -- in this case, version RIPOFF (which was used in 14 worlds). Not much else to say, other than most people used the update to Nomo7.
Color Toolbox: 2.63% (113/4291)

Another toolkit that took off because it was around early enough. I love how the color fades take up huge swaths of space, while the floors are just dots.
MORESTK: 2.03% (87/4291)

We've dropped below 100 uses now. The most popular boards from MORESTK are More Passages (87), which provides blinking passages and passages with black backgrounds; Text: B, G, Cy, R (59); Text: P, Y, W (47); Forests (44); and Empties (33). The other stuff gets some use, but it seems like a lot of it is just novelty material. And I don't know why the screenshot says "*NEW STK".
DirrCo Krazie Kitt: 1.96% (84/4291)

All the Krazie Kitts are radically different, especially 3 from 2. But for some reason, I lumped them all in one category. Not that it matters much, as the first two Kitts only got 8 uses in total. I love the look of the zigzag palette, but I think it's missing some colors.
Suburbia Triumphant: 1.91% (82/4291)

The most popular toolkit that's so full, there aren't even any separators. I said earlier that if you leave empty space in your toolkit, someone will eventually fill it with something. Turns out that's true even if you don't leave empty space.
A.I.Z.I. Advanced with ZOP: 1.82% (78/4291)

By now it should be pretty clear that I'm being really sloppy with categorization. This toolkit is ZOP, except with a few A.I.Z.I. items added (A.I.Z.I itself being a board from STK with a few items added). But I gave it its own category, I guess because it looks like someone else made it, and because it got substantial use. Like I said earlier, my data-gathering is severely flawed, but it's probably good enough.
Paranoid Machinations: 1.75% (75/4291)

All versions saw some use, but v3 got used the most (37 worlds). I think v3 is one of the earlier versions, seeing as Nadir was still keeping track of version numbers at the time (latest version is paramach v. infinity^infinity).
Dude Scott This is Josh: 1.70% (73/4291)

Again, why does everyone put the horizon blends on the right side? Is it just tradition?
pisces iscariot: 1.51% (65/4291)

Okay, so not everyone.
DarkMage ColorKit: 1.17% (50/4291)

Looks like another early toolkit. There were two official versions, as well as a couple of modifications by Nivek (found in 18 worlds). Again, I was sloppy with categorization, but I really don't want to (1) come up with some formal rules, and (2) count toolkits again.
Zenith Tool Kit: 1.17% (50/4291)

Another toolkit from Zenith! This one went through a few different versions, each of which saw a fair amount of use. Tied with DM ColorKit for popularity, though it would win out if Nivek's modifications were classified separately.
Toolkits with fewer than 50 uses (skim for vanity purposes, if you have a toolkit):
Colors R' Us; dexkit; RooKit '98; Spectracolor; AKWare Toolkits; BenKit, BenKit 2 (BQKiT); Newt's Toolbox; <3\/|$|0/\/ (shades toolbox revision); textures by eJECTION13; divided; Flame, Inc. Color Kit; FutureWare Blending Kit; MadTom's ColorKit
Toolkits with fewer than 25 uses:
Scheme Toolboxes; ZZTek Colour Kit; Chase's Toolbox; HM's Wonkeriffic Toolkit; Wayward's Toolkit of Grooviness; WEIRDSTK; Raichu's (Hazard's) CircuitBox; MNMZ Toolkits; dexter's monotools; DGE Color Kit; Earthquake Toolkit; Rob Pragt's Toolkit; abbloipp; The ZZT First Aid Kit; dexter's kolours; barrel 'o fun kit; dexmono; Embassy Games Color Center; MadTom's ZZToolKit; PARASITE'S TOOL KIT; VisuoFunctional Spectrum; ZZT Palette Plus; DrCrab's Crammed Board; Nomo7: vripoff; yllek's kewl color board; ALL v1.0 for ZZT; Bocco11’s ZZToolkit; CorPuS HeRmetIcUm; glt-kit by tboT; D.'s Box o' Junk ::: Akim Prod; dexscams; SIMBA SEZ ROAR; Small ZZT Toolbox; The Hopeless Ascii Toolkit; 3D toolkits; dexter's pepsi-kit; Magical Mystical ColorBox; Quantum's Toolkit; ZZTek Color Board (kev carter); ZZTPhoenix Graphics Toolbox
Toolkits with fewer than 10 uses:
JM's All Purpose ZZT Toolbox; KPCK; packboard.v1.aetsch.if.2000; SGP ColorKit; Vecchio's Toolkit; Mystickal Color Toolkit; Team Smiley X Color Kit; Terrain Toolbox - Ice; EvilMario ZZT-Tool Kit; Friday Night Fever; Herbal Awakening; Raptorian's Toolbox; rom toolkit; Tripping Color Kit; Ultra Colour; Zenith's Personal Toolkit; Bonus Palette; Dave's ARG! PG Tool-kit; GameMstr1's MegaShades Board; MRFLOYDS COLOR BOX; Nuero's Toolkit; StreamLineSTK; the kit of iiiiiiiiiiii; Total Fades series; WIL STK; Random Inc TK; A.I.Z.I ToolBox; Creemy Chock n' Cheez Froot Lumps; HGSI Color Editing Kits; KZT - Color Kit; Mystical Winds TK set; Phobos Inc toolkit!; SIlver SPectrum v. Karma; WinS Toolbox; _Underscore_; Dsone's Kit; Shaft Toolkit; UseLESSS ReDUNDAncYYYYy; BesTK; Bucket Toolkit; Chris's Toolkit; Leamas' Toolkit; Matteo Box; Mega Akim Prod. Board; Mondo SaxxonPike ToolBox; Redmage PSYCHO Toolkit; vin3y $hades Toolbo><; ZZT Painter; beef's ultra funky tool kit; Da-Caelin-Kit; davr0s toolkit; Dr.J2000's Sexy Toolkit; DTK (by PKP); FreeZerBurn Toolkit; Headache-Inducing Evil; myth's palette; Noboyuki's Tool Set; starbux toolkit '01; TEENSPIRIT'S TOOLBOX; The Everything Board; UltraTK; VINEY80X; WCB's Toolkit; ZZT98's Color Kit; 2z + t; Baron's Apocalypse; Black Night Toolkit; Blend Box; Cheetah Colour Kit; Clockwise (p2) and Still Head; COLAHZ! (unknown); Compressed TextKit; dark_visions Super Tool Kit; Develins s***ful toolkit V: huh?; dexter's disco-stk; dexter's ultra kewl awesome color kit; Dwa's Tools; Fake and Invisible walls; KgC Lab; Knoxville Kit; lemmer monochrome; lemmer monotools; LeMMO14's Toolkit; MeWho's CrayonBox; MIG Toolkit; Myst Objects; Mysterio3000's Megafade Color Kit; Mysterio3000's Premade Color Kit; NOC List Color Kit; Nova's Toolbox; Oddboink's Colorbox; Oddboink's Toolkit; Ook-Tool-Kit; PColor; Rogue Mini-Toolkit; Ruffians blending kit; S TEA KAY; Shujtkit; Silent Orb Crayon Box; stk - blinking passage; T-6 Cool Blends (T-bone); T-6 Tools 1 (T-bone); Tbot's Texture Toolkit; Tbot's Toolbox; Terrain Toolbox- FIRE!!!; The KjKit; Trilink Shades Kit; Trilink Toolkit; Ultima Color Board; Vampy Toolkit; ZZT By Us Color Kit; ZZT Rainbow
Apologies for the long post! If you want raw data/program code/other stuff, let me know. I might do some more stuff with ASCII charts later, but right now, I've seen all the in-game utilities I can stand.
--Edit by zamros 2/15/15, fixed belsambar links.