A couple of mates and I are going to try "Busking" in our local town soon, with the difference that there won't be any hat/guitar case/tin cup etc. for collections because we're doing it for the fun... and to get a little folk on the streets.
The relevant laws that we will be breaking are pretty obscure - stuff like causing a disturbance and obstruction etc. but I think we're ok so long as we move when moved on.

CamoJohn