'tis embarrassing to admit for some of us who know there are real distance geeks out here. I've done some doubles with some change, but no really long rides yet.
The mind is willing and doesn't care what the body thinks, but the circumstances (i.e. boss, wife, and travel gods) have not yet allowed me to do something really long yet. A 24 hr event is on my list of rides to do, but that will probably not happen this year.