I've made a few personal mods before, nothing big; some character skins for JK3, maps for the SAGE engine (Zero Hour and Tiberium Wars specifically). Making maps is a lot of fun for me, especially, tho I'm in no way a pro at it yet. I'm thinking about posting stuff here as I work on it. Who knows, others might like it too.
I'm currently writing the design document for and creating a prototype engine of my game idea, "Codename Vast". Generally speaking, it will be an MMORPG.