The Saudi and UAE governments are thinking of banning certain services on BlackBerry phones, as theyare encrypted and communicate to foreign systems.
Joe reminds us that while encrypted communications can be used for nefarious purposes, they can also be used for good. Phil Zimmermann, inventor of the common encryption software PGP feels the same way.
Indeed, they are used for good far more than for evil, and their use is almost ubiquitous: essentially any site that deals with personal or financial information is SSL-encrypted. Gmail uses SSL by default, and now even Google Search is available over SSL. Most instant-messaging clients use SSL between the client and server, and Skype uses transparent, end-to-end encryption for all voice, video, and chat messages, as well as file transfers.
In a way, crypto is not unlike firearms1 : it can be used by bad guys plotting dastardly deeds, but its benefits to society are considerably greater than its drawbacks.
In fact, I consider strong crypto to go hand-in-hand with free speech: being able to speak privately (and, on a related note, anonymously) is one of the strongest foundations of liberty. I hold this believe so strongly that I regularly use and encourage others to use strong crypto in their everyday lives. For those wishing to contact me securely, my PGP key is available here. One can also send me an S/MIME-signed message and I will reply with a signed+encrypted message.