One of the new features coming out in ios 5 is multitouch gestures. You can close apps with a 5 finger 'swipe', bring up the app bar or switch between active apps with a 4 finger swipe.

There's a way to get it now; apparently it was in the dev version of ios 4 but for some reason they didn't put it in the release version. I've been using it for awhile and really like it, I seldom use the home button now. Very easy to do. The instructions say it's for ipad 1, lower ios version than is out now, but I used it with an ipad 2 and the most up-to-date ios and it worked fine.