I am not a CRNA but I have been using a PDA for many years and now I am using it for drug reference and as a medical dictionary. I have found that a PDA with at least 16 MB of built in memory with an expansion card/memroy stick slot to be sufficient. Palm PDAs are easy to learn. The other option you have is the pocket PC which is a small PC and can do the things a PC can (Palm products can too) and these aslo can be used like the Palmn PDA, Dell has a good selection. As for the software, I am currently using Epocrates which costs about $200 a year for the subscription and is great. They also have free software which give you a drug guide and a few other things. Pep-id and lexicomp are the other PDA software provider that nurses use. Good luck and have fun.