I think this is going to be a controversial one 
The thought of using an anti-perspirant gives me the creeps. To me, it's like using a product to cut down on your saliva, or other secretions, and it just seems unnatural and wrong. I haven't used it since I was a teenager and got fed up of all the white marks, not to mention the scaremongering about products containing aluminium.
I'm slightly more comfortable with the idea of deodorants but again, I hate the thought of slicking my armpits with a sticky product just to smell a bit more like a toilet freshener. I'm 'lucky' to have the dry earwax gene and everyone I've asked (I did a study as part of this at Uni too) says they can't detect an odour, but I think I'd feel this way even if I did produce BO.
I usually just spritz a bit of perfume and get on with it. To me, sweating is a beneficial thing for the body.
Does anyone else feel the same or am I completely on my own here?