I also use the Crystal! http://www.thecrystal.com/
it's a mineral salt, it deodorizes by killing the bacteria on the skin. it is NOT an antiperspirant.
I love this thing. I've been using it for about 3 years and It WORKS. I thought that i needed to use antiperspirant/deodorants because i sweat a lot, but the antiperspirants actually make me smell worse than my natural smell.... so i gave up on those and just use the crystal. every other week i'll take alcohol to my underarms to ensure the bacteria is under control and daily, apply the crystal after my shower. always fresh, never have a problem.