I've got Olfa cutters all over the place, however, my Favorite is the ego one from Martelli. Since I'm right handed I've got the red handle one, they make one for 'lefties' also, I think the handle is black.
My chiropractor and friend started using one and she now swears by them. I notice the difference on my wrist not being sore. They are a bit pricey but worth it. I don't know if you can get them at JoAnns with a coupon or not.