I spent hours on KDE Sokoban, though.

Sokoban is one of the games I spent most times with. There's one level in there which 3 of my collueges reported as impossible; It took me a few days to get the answer...
The problem with minesweeper is that it becomes too routine. Once you get it, all games are the same...

Sokoban is also available for every platform I think. I even got a real cool sed-version...