How do you get rid of flea on cats?

Wow! If that stuff works in FL, it must be realy good! I've heard that diatamatious earth (sp?) works for long term environmental control of bugs like fleas, because the particles of the powder have razor edges that cut the bugs and kill them, but these particles are too small to harm humans or larger animals. At least that's how it was explained to me. I've never tried it.