Weeeeellll I got pretty bored. So, with some help from Data himself, I cobbled together a list of every build of CC available. D.I.R.T, unfortunately, went out with the attachments when we moved servers. If anyone has it, please message me. However, I am still able to do a basic synopsis of what each new build brought to the table.

From the top, now.

Build 1
Literally nothing more than a technical demo.
Notes: Splash screen, but no .rte index.
No main menu.
Gold collection is old-style.
Rockets exist, as do Long Cannons, Blasters, SMGs, Pistols, and Shotguns. That's all.

Build 2
Build 1, but with: an .rte index

Build 3
Build 2, but with a nonfunctional Buy Menu GUI.

Build 4
Text on startup. First hints of Main Menu. First bit of sounds.

Alright I'm tired so I'm not going to finish the synopsis right now.

However, I will give you links to every CC build.

Build 1
Build 2
Build 3
Build 4
Build 5
Build 6
Build 7
Build 8
Build 10
Build 11
Build 12
Build 13
Build 14
Build 15
Build 16
Build 17
Build 18
Build 19
Build 20
Build 21
Build 22

Those keeping score may notice that Build 9 is not present. This is because it was the IGF build, so the URL did not fit into the pattern used to get the other builds. However, courtesy of Google, I found a .torrent of it, and so, I give you this:
http://www.gameupdates.org/details.php?id=757

For those worrying about stability, I promise I'll be seeding this as much as possible. And, no, there aren't any viruses on it, nor is it illegal.

I demand money for my pain. Now. Not really. Nice job Grif, this will be enjoyed by everyone. A sticky for this would be nice.

The point of absolute admiration has been reached.

couldn't find build 9 anywhere, thanks... although I hate torrents and need to download a torrent downloader again. on that page contains a link to http://www.bitlet.org/ which downloads torrents without a torrent client woo.

Digging up the D.I.R.T on cortex command.

Utorrent is faster then bitlet.
Don't ask how i know these things.
(i wanted to get this free indie game, but the site was down so i did some research)

This is my first time ever playing build 1.

Cortex Command was awesome from the first build, up.

Whenever you die, a new rocket comes
to take its place, automatically,
fresh for the chucking of the gold.

There was a certain sense that anything could happen, until build 14.

I've got DIRT 13.
The problem is, I can't get it to work.
So I don't really know if this will be any help at all.

Nice to play good old b14 some more.
And to try out B1.

Have I mentioned that I love you? I have been looking all over for build 9. I love you

your gonna hate me for it but I had all the D.I.R.T builds but deleted most of them because they didn't work.

I know I'm going to be called a noob for this but what is the difference beetween builds? All I thought was that a build was like a update and when a new build came out it updated it but aparrently there all completely different games.

Each build adds on to the previous. Some people like playing the old builds because they like to see how far the game has progressed, or because some older mods are only compatable with older builds.

Whee, some of the DIRT builds have been added.

Hurrah! Now I can look back even further into CC's past! I tried playing DIRTB1, it said it could not set the video mode on an error window. I was looking forward to seeing that weird old visual style in the earlier DIRT builds too... I did try B22 though, that is fun.

Its kind of weird to see the same visual style in DIRT. I remember seeing a lot of pictures of some different kind of bunker module, kind of greyish looking. Or was that an old mod?

The images for that bunker are actually still in the Base.rte folder in the latest build. I'm pretty sure it was used in a few of those first ones.