I just read a thread here about Leatherman's Knifeless Fuse being not OK for airplanes. I believe the lucky owner had to give it up to the TSA agent.

Recently while traveling, I forgot to take out my Spyderco Jester which I normally carry in my valet. Of course I was stopped by TSA people at the checkpoint. Not wanting to give it up I went over to the Checkpoint Mailer stand and mailed it to myself. I received the knife within 3 weeks. It cost around $10.

I don't think they have this service at all the airports, but here is a list:
http://www.checkpointmailers.com/airportlist.php