Re:Which is best? (Score 2, Informative)

If speed is king, consider a tmpfs filesystem periodically rsync'd back to a drive.

If that's a little extreme, XFS is probably the way to go. Ext3 is good for /, since you still have an ext2 way out, if you need it. ReiserFS works well with small files -- it makes a great proxy cache. XFS is good all around.