Well, I'm a new convert. I ditched the 18 blade Mach42 stuff many years ago, switched to cheap two blade disposables for a few years, and I finally took the plunge back to the 1890's and got myself a double edged safety razor a couple of months ago.
The blades cost about 10 cents and in my two months of experience they last me about a week before I feel like replacing them. So, that's about $5 a year in blade costs. Granted, I did go back to using shaving cream, something I hadn't used in years, but I'll probably get away from doing that now that I know how to use it.
It's a little slower for daily shaving but if you skip a few days it doesn't clog up like a disposable does.