If your on the Playstation Network then psp's are really good.
My son has one, and you can do some cool shit with it (esp the psp go), the older type psp's (the ones that use the umd disc's) require silly video conversion for vid files and other stuff like that.
Having access to the psn gives you tons of games, apps (gps type things etc.), digital comics, movies, mp3 etc.. You can also control your ps3 with it, so if he's lying in bed he can access the ps3 via the network, and watch/listen to any content stored on the ps3, as well as using it for surfin the web.
The games I feel win over the other portable consoles, as they develop psp versions of ps3 (and old ps2 and ps1) games like God Of War, Grand Theft Auto, and well just about all of the big games really.
The psn does monthly "free" games and media, and if your a game geek, you can create an American psn account, and get access to tooooons more stuff via the USA Psn.
Graphics and audio are really good too, the only gripe is they have changed the generic usb mini port to a "playstation" only usb plug/port. However you can (by purchasing the right cable) plug the psp into a tv and watch/play on a bigger screen. Play link up games via wi-fi. It's not the sturdiest piece of kit, but what portable electronic device is really? (dropped your iphone?)
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