>The compact framework does not contain (hardly) any crypto stuff (System.Security.Cryptography). I have been using a class I wrote to encrypt and decrypt text (which used a lot of stuff from System.Security.Cryptography). Now I need to share my encrypting and decrypting with a PPC application and since a lot of this is not available in the compact framework I either have to write my own or use someone elses.

I'd suggest checking out OpenNETCF:

http://www.opennetcf.com