I've been runningn Windows without swapfile for the last week. The performance jump is actually noticable; and my harddrives probably feel a lot better. So far, no applications have complained about the lack of memory, and I generally have around 400 megs of free RAM.
I doubt it would work good on low-memory systems, though.
Has anyone experienced any major difference between 768 and 1024 megs of RAM?.