I'm riding in Texas. It's quite hot and I sweat a lot on my commute (52-mile roundtrip). I keep several weeks worth of work clothes at my desk (khakis, slacks, golf shirts and oxfords). I drive about twice a month and switch out clean clothes for the dirty.

Shower before leaving home. If you sweat when you are clean, you will not stink nearly as bad as sweating when already dirty.

If you can keep your hair really short, you can clean up more thoroughly. I have my hair buzzed and wash my hair, face and forearms in the bathroom sink.

Baby wipes take care of my pits and crotch area, (a splash of baby powder down there is a good thing too). I put on fresh deodorant and I'm good to go. In the hottest part of the summer, I do use Axe body spray as well.