So I've run across a program called hamscope it does BPSK QPSK CW RTTY MFSK16 and Packet. It also has many many settings. You can basically use it to do IM/Chat/text over HAM It's a great program I've only barely started making it work. Right now my problem is getting it to automatically key my radio when it sends. I've got to learn the settings right now it's set up as I type it transmits I want to change that, anyway I was shown this program a while back and lost it but found it today doing a back up and wanted to share. I'm going to share a link to QSL that has the download link, not sure if that is allowed but if not just delete the link mods.
http://www.qsl.net/hamscope/This has all the needed info to get you started. I think if this is set up properly and you tweak your setting just right it is the closest thing you will get to "crypto" or encryption and it is pefectly legal because anyone with the right settings "could" decipher it. Either way a great program.