Thanks for ZZT Tim. That game changed my life when I was starting high school in the mid 90s; it was one of the ways I learnt to really have fun with computers as well as to program and make my own games.
Also, Unreal Tournament still holds a very fond place in my heart. I don't play games these days, but on the very rare occasion I feel like it, that's one of my major go-tos, just for the nostalgia of Facing-Worlds ;)