Thanko has announced the "PSP Wireless Headset," a set of wireless headphones you can use with your PSP. They're pretty cheap at 1,480 yen (~$13 USD), but there is also a pretty big downside: they don't support stereo audio. This is quite a downer for those of us who thought this would be really awesome to use with PSPRadio. FM is used to transmit the audio to the headphones, so you don't need to worry about it interfering with your WiFi.

Find out more about the wireless headphones for PSP from Thanko at http://psp-vault.com/Article331.psp.