A web TV show called From the Shadows did a short piece on how to add an external antenna port to a PSP (warning mild language). I think they were getting a connection at 100 meters or something. My computer media is acting funny but the movie is
here. Happy surfing!
(I love how this emotion looks like my avatar) If you do do this make sure you know how to solder and sand with fair precision. By the way I love what you did, you might want to look here for other
things to do to your PSP.