There are two ways of thinking in terms of location-based games/services on the Sony PSP. The first track is to wait for the proper GPS adapter Sony is working on, scheduled to be launched before the end of 2006 (as written in the US PlayStation Magazine). It might be a USB adapter already presented at E3 in 2004 //thanks Sylvain!):

(picture via gamongirls)

The second track is of course to lack at the undergound world: gpsp is a hack that turns the PSP into a GPS navigation system, developed by ?Art?:

Hi Guys, this is the first version of a program for the PSP that provides a practical GPS Graphic User Interface (GUI). The GPSP software for Sony PSP runs under LUAplayer 0.11 or later. LUAplayer is free. If you haven't downloaded it, you will need to get it running on your 1.50 firmware PSP in order to try this out for yourself.

Well, as it exists at the moment, it will allow you to view data from a GPS Mouse on the screen of your PSP running the GPSP program. This occurs in real time, however there is a delay from when the data is received by the microcontroller circuit, and retransmitted at the slower rate to the PSP. The pic circuit is also filtering information from the NMEA sentences transmitted by the GPS mouse, and discarding any information that GPSP doesn't use so that minimal bytes are retransmitted by the pic circuit to achieve (or try) the fastest transmission that GPSP will interpret.

Why do I blog this? if the first track is released this would be a good step towards mass-market console with location-based capabilities (I'm not talking about cell phones here).