Does anybody here play Garry's Mod?
garrysmod.org - Garry's Mod Related Files! Welcome to Steam
Get mods for it off of garrysmod.org
Get GMod off of Steam. (You need Counter Strike: Source as a source engine, together it's $25) You can also use Team Fortress 2 for the same cost.
If any of you play GMod, what's your Steam username?
For you that don't:
Garry's Mod is a physics sandbox, where you constrain objects with welds, ropes, hydraulics, etc. You take different objects, weld/constrain them, and you can make almost any contraption. You should get addons such as Wiremod(creates electrical circuits), and PhoeniX(Construction model pack)
And if you want to kill/trap people, try building Cju's simple traps (You can find the videos of them on YouTube)