I've made a map called acquarium with another great italian mapper, many CTF maps called KappaCTF1, KappaCTF2 ecc ecc. I've made a colosseum and, my proud map, the best I've ever made is MisteryCastle. That map required ALL the 2001 and we were 4 mappers with basic modeling skills (plus 2 modeler). It's a series of riddles and enigmas that makes you find some buttons that open certainly door in which you can discover new things and button by button, at the end you find the tresure: all weapons (includes bfg and grappling hook), plus quad damage and yellow armor and etc etc etc etc etc etc etc etc etc, and 1.000.000.000 points.
The "history" tells about a king disappeared from the castle and who finds the treasure will become the new king.