4 Bars With Gas Springs have been used before, and quite effectively. However I feel like not in the way your describing.
http://www.chiefdelphi.com/media/photos/26796
http://www.chiefdelphi.com/media/photos/21477
http://www.chiefdelphi.com/media/photos/27982
Thats 1902, 1369, 217 in 2005, 2056 in 2007 just a few examples that I can think of.