is there anyway to attach external keyboard Peter?

Yea It has USB and Bluetooth

nice, so in hindsight u could possibly use a PS3 controller like Kevin was saying you can do with the GO?

should be able to, i'd think. might be a little trickier than normal to pair them, but not by much (and if it is, it's only because sony likes to do things weird. pretty sure you can only pair the go and ps3 controller by using a ps3, or  at least that's what i'd read)
edit: seems you no longer need a ps3 to pair with a go, at least according to a youtube video. guess i'll get around to that sooner now (i don't have a ps3 and really only would play a few games on one)

If only PSP had MIDI out... ah well.

Curious, is there any difference in the audio quality with a GO as compared to a 2000 or phatty?

they seem comparable, though there was some time between when i had the previous models and when i got the go. what i still want to test at some point is load times (psp go flash vs psp 1000/2000/3000 mem stick pro duo)

I actually couldn't get my PS3 to work, but my 8bitdo snes pad works fine.