I've worked with Valve's Source SDK for many years now, and have created a few good maps for Team Fortress 2. I'm working on breaking into the Amnesia community as I've wanted to do some games/mods/maps/whatever with an actual story to them.
A map I made for a surf map making contest at lowlagfrag.com.
Took 2 months. Has a custom server plugin that rewards players who surf farther in the map with addcondition effects from the cheats list. (health steal, for example)