Mac + iPad: iOS 4.3 was supposed to add really useful four-finger and five-finger multitouch gestures on the iPad, but unfortunately they weren't included in the official release — or more precisely, they're in the release, but you can't enable them without a little know-how.
YouTube user myjailbreakmovies walks through the process in the video above, which involves downloading Xcode for free and enabling developer mode for your iPad. You can also accomplish this by downloading Xcode from the Mac App Store for $6 — a process our pals over at Gizmodo somewhat sensationally detailed. (I find it pretty hard to believe that Apple cares whether or not you know about or enable these features.)
It's a pretty simple process, and when you're done, those handy multitouch gestures for swiping through multitasking applications and jumping to the home screen (you can see them in action here) are all yours. The video says it's "iPad 2 multitouch gestures", but this should work on any iPad running iOS 4.3.