Well, the method of sending it back to yourself in a padded envelope actually worked for me once, a very long time ago.
I used to travel with a Cold Steel folder with a 3.5" tanto blade way back in the early 90's. I had absolutely no problems from anyone while having it in my fanny pack while going through security checks at airports all over the world, including Singapore, Hong Kong, Tokyo, San Francisco, New York (Kennedy), Los Angeles, etc.
However, the one time this happened, I was leaving Canada from Toronto International, and Security there wouldn't let it through. They wanted me to put it in my check-in luggage, but by this time, all my bags had already been checked in, and I was almost at the boarding gate. Luckily, the security officer was nice enough to offer me a padded envelope to put my knife in, and told me that she (yes, it was a lady), would send it for me. I was leaving for Singapore on that flight, but had the knife sent to my friend's place in Chicago instead. I was actually resigned to losing my favourite knife, but it actually showed up at friend's place a few weeks later. /ubbthreads/images/graemlins/grin.gif
Obviously, this happened a long time ago, and the lady security officer was generous enough to do this for me as a favour. I don't know if the current crop of TSA hired security "goons" would do this for you though.
Ahh... I really miss the relatively "care free" way that air travel used to be before 9/11..