This is still the best puzzle game ever made, in my humble opinion.
They march and march and march and you need to guide them to their goal. But the real genius was the way the game forced you to think outside the box. There were only 7 or 8 or so tasks to assign to the lemmings but by the end of the game you realize you have done all sorts of things you wouldn't have thought possible.
I still haven't beaten the last stage (125.) I'm convinced it's IMPOSSIBLE!
Out of 7 user(s) who marked the game in their log: