I have been gaming since 1980. I have never had a more visceral blown away reaction to a game than the first time I played Doom. We even setup a LAN in our dorm so that we could play it multi-player. The only other computer experience with a similar impact was seeing web pages for the first time and realizing that my parents would be able to use the internet with them (no need to learn usenet, ftp, archie, gopher, and all of the command line utilities that I used). Doom felt so revolutionary.