About 2-3 times per week for me, and I'm NEVER noticeably stinky whatsoever. I've asked my wife (and a few others I trust) if I just don't notice it, but they've all said they'd never know I didn't shower daily. I use the same towel for two weeks or more unless it gets tossed in the hamper. I also use barely any soap. I use it for one particular... uhh... area. But the rest is just a wipe down with a washcloth. I'll only use soap if there's some kind of grease, dirt or grime that needs some assistance.
I'm trying to figure out a shampoo solution that I like. Regular shampoo dries it out too much, but the home made ones have all left it feeling very oily or waxy and quite nasty. Any suggestions there?
And I'll say this: my skin is never dry and it's very soft even though I'm constantly getting into some kind of plumbing, wiring, fixing brakes or some other kind of work. My wife comments on how soft my hands are for someone who is always using them for some kind of project or task.
I think that in general, we over-bathe or at least over-soap. I don't think we were meant to rinse away all of our bodies natural oils every day and I think we screw with our systems when we do so and have to compensate with products.