I'm a ZDoom user who has been modding for about two years now. I learned to write DECORATE entirely on my own, without the wiki or forum.
Mods Ceeb has made
The Compound, a quick and average-rated mission-based map. It's not half-bad, I suppose, but I admit that there's better stuff.
The Wizard's Study, a Hexen deathmatch map. Pretty cool if you ask me, also pretty small.
On top of these, I have two smaller projects I'm working on. A heavily scripted Doom 2 mod that uses only resources from the IWAD (and gzdoom.pk3) called Resource, and a more fleshed-out, hub-based mission set called The Canyon Outpost, which is my less-suck-plz attempt to make a mod like The Compound.
Stupid shit Ceeb has made
Rocket Propelled Impse, exactly what it says on the tin.
Skidball, a game of zombie soccer for two. Pretty fun.
Morshu Strife LAMP OIL! ROPE? BOMBS? YOU WANT IT? IT'S YOURS MY FRIEND, AS LONG AS YOU HAVE ENOUGH RUPEES!
I also have a resource thread which contains texture packs I ripped and useful chunks of code I've thrown together over time. You can find it right here!
As an aside, since being banned from ZDoom I can't actually update that. Find me on Realm667 if you'd like, and drop me a PM there if you'd like to see my catalog of resources.