Wow, this is an old topic. SSNTails even posted in it twice, once a month ago, the other in 2007.
I think I came across Demo 2 through SAGE. I was blown out of my mind. 3D fan games were extremely rare back then (there were none, apart from Sonic Doom and SRB2 itself). I kept following SRB2's progress until the release of Final Demo 1.0. I remember seeing the picture of THZ2 which SSNTails posted on the front page and being awestruck. Mystic's level pack, Mystic Realm Mystic Way Mystic Realm was really going places, too, but it was some time in the 1.0 era that Mystic Realm 4 was released, coinciding with the release date of the new version of SRB2 itself. I remember I downloaded both, but Mystic Realm finished in very little time while SRB2 was taking forever (no broadband back then), so I was very much peeved I had something which I wanted to but could not play.
I was left without an internet connection during the 1.04-1.08 period, but I regained it just days before 1.09 was released. That's when I played my first netgames, and a few months later decided to join the forums. I was very much still a kid at the time, so.