Now and then I see someone asking about these Dritz rotary blade sharpeners. I've been using this one for years now and I love it. It might not get the blades as sharp as they were when they first came out of the package, but its gets them sharp enough for me.
Honestly, I sharpen the same blade over and over and over again. I do a lot of cutting, with my die cutters and my rotary cutters, and I'm too cheap to buy new blades as often as everyone else tells me I should. And since the sharpener works just fine, I don't. The blade that's in my cutter now has been in use for over a year.
When I first got the sharpener, which was a birthday gift from my mom, I was scared to death of it. I just knew that there were band-aids and blood in my future. But I've never had a bit of trouble with it. My big problem is putting the cutter back together, and that's going to happen with new blades or old ones.
Do you sharpen your blades? Buy the cheap carpet cutter refills from Harbor Freight? Wait for sales and coupons?