I usually format once a month or so to clear out the garbage from whatever software/settings I've been testing. Any important files are held in "My Documents" that I've re-directed using TweakUI to a second partition so that I don't have to restore them from backup whenever I do this. Microsoft also recommends having the swap file on a seperate partition from Windows for increased performance, hence my setup choices.
I only have a single drive installed at the moment so it makes more sense for me to do thing's that way rather than a single partitioned drive.
I only have a single drive installed at the moment so it makes more sense for me to do thing's that way rather than a single partitioned drive.