Delirium is a handle I used back in the mid-90s when uploading Doom deathmatch demos to ftp.cdrom.com. It was as in "I left my opponents in a state of delirium." There was also somewhat of a reference to Neil Gaiman's Sandman series, which I was reading at the time.

The name stuck, and when Quake came out, my gang formed "Clan Schizophrenia", who's members were Delirium (myself), Confusion, and Paranoia. As a clan, we failed miserably, our one good experience being a meeting at OSU's computer lab where we fought students from another campus in their lab. We had a snazzy logo of a yin-yang symbol, slightly skewed, with three circles on one side, and none on the other. To be a kid again...

I kept Delirium as a handle to use on newer forums to replace my old 80s dial-up BBS handle, Reflector. I find that both are taken quite frequently by kids, so if you see Delirium on another forum/IRC/what-have-you, it's probably not me. (If you see Delirium on the road, kill him.)