Originally Posted by SilentKnight

Well-worded and sounds intimidating enough. I'd say it should do the trick for ya'.

I have a few of my own that are similiarly worded - but they're on my other system at the moment.

I had one where we demanded monetary compensation for the loss of revenue based on the copyright infringement of several of our pics on the mainpages of a paysite. Lost track of that particular letter, but it was well-worded enough to get settlement payments from two separate individuals at the time. One scared the guy so bad he called us long distance from Great Britain at 3am to discuss a settlement (he'd forgotten the time difference, lol).

Good luck. Hope the letter has its desired effect.