Martelli's rotary cutter is ergonomic; I like it a lot. You can see video demonstrations of it at their website:
http://www.martellinotions.com/
Another option is the Accuquilt Go! die cutting system. A lot of quilters are opting for that because most of the work is done with a crank. The website is:
http://www.accuquilt.com/
There are a lot of video demo's of the accuquilt Go! on Youtube also.