We live in Portland, Maine... I haven't run into any big problems with people trying to unbolt my speakers or anything....
I work at a big company, so no one will steal the 'ped at work, but if I go into school or to visit friends I plan on using a 'U' and a cable.
A big part of the design has always been the removability-- I didn't want to get left out when people hit the trails on mountain bikes. That's why I went with the pannier pack and bracket mount speakers... I could pull off everything but a couple of brackets and wires in a couple minutes and it went back on just as quick.
I'll use that same design concept when I convert it to the new ped-- I always think how I can make it ''quick remove".
I think that having a 12v air horn will be a lifesaver to wake up ignorant drivers. I'll get a nice chrome one and conceal the air tube and compressor.
I will keep you posted and as soon as the 'ped arrives and is ready (by next friday the 11th at the latest) Pics will soon follow!!