Any criminal who conducts business over Skype pretty much deserves to get caught. There are dozens of communication methods that the police probably don't even know exist, if you use one that's popular and centralized, you are dumb.
I always thought in-game chat like in the scrabble and pictionary rip-offs for Android/iOS was a pretty clever way to hide communications. I'm sure there are games even more off the radar with that capability that most wouldn't think to track...
How about thins like Xbox Live & PSN? Do they have secret backdoors?
