There was one time that I was at a church in Minneapolis, and during the worship service 2 of the people behind me spoke in tongues. They didn't go on for a long period of time, they just each said one phrase and that was it. I can't explain why, but for some reason that was the one time that I heard it and felt that it could be real. All of the other times that I've heard it, it always sounded like babbling and it seemed like the people were just doing it for show...
I've never done it myself, but I think that the writings of Paul indicate that there are unrecognizable tongues which come from the Spirit, and that speaking in tongues does not always involve a known tongue or must always be used to break a language barrier.
I also don't understand how people still go on and on about it being a gift that everyone receives, when scripture states very clearly that it isn't. You can show them the scriptures, and they still go right on believing what they want to believe.