Garret and Kalia, I'm right there with you. Play without flagging mines, lose interest because my new mouse doesn't work as well for it, etc. At one point, I would even adjust the mouse sensitivity and the screen resolution just for Minesweeper games (easier to read = faster).
As long as we're talking records, my best Expert win was under 90 seconds (I think 87). At some point, it becomes helpful not to flag some of the bombs and to rely on them being exposed when you hit the last safe square. For speed rounds, I would also randomly click a bunch of spots until 2 separate areas were revealed. Little tricks add up to small but useful time savings. ^_^ Sadly, I can't come close to those times anymore because I'm so out of practice (on the order of a few years).
Congrats on finding an 8 by the way. I'm not certain I ever saw one of those, though given all the games I've played, surely it should have happened at least once....