I've seen some VERY expensive anatomy programs for PDAs, and I mean very expensive. There is a good flash card website that I like. You have to pay a one time life membership of $19.95 to join but once you've paid you can download anyones flash cards or make your own. They advertise that they have over 7,000,000 flashcards! They can be printed out but there also is a way to make them for your PDA. The directions are online & are very easy to follow.
The website is
http://www.flashcardexchange.com/
If you don't want to pay, you can still see the cards & use them online. You just can't make your own or print them out.