Yes, Crassulae pretty much require pruning, they can get really goofy looking if you don't (plus you can give everyone you know a Jade plant of their own- we must give one away every 2 weeks or so)
One plant that doesn't like pruning too much is S.purpurea, though- the first (and so far only) one I bought from home depot was sorta going dormant, and using my "plant instincts" I snipped off all of the (proper name is escaping me totally right now) "dormancy scapes" and killed it outright

But occasional stress seems to do wonders for most plants, as most people here likely know cactii won't even try to flower if they aren't kept really dry and kinda cool over winter

And of course the classic Snake Plant, which doesn't seem to need anything [img]http://www.**********.com/iB_html/non-cgi/emoticons/biggrin.gif[/img]