I've managed to sort out a hull as a basis to make a start, I'm going to use one of the hulls from an old Lesro Gemini catamaran...24" long will be a real challenge, but I'm pretty sure it's doable(is that a word?) using micro radio gear.
The engine I have a 1/12th Ford V8 out of an old Mustang kit I found in my cupboard, I reckon a 280 sized motor hidden under some deck cargo will be more than powerful enough. A 5g micro servo will swing the V8 to give me steering, a micro rx, an Action Pico esc, and a small battery pack hidden up in the bows should do the job nicely. It means having a conventional prop shaft under the boat, but once it's in the water it won't show. Either that, or one of those little clip on motors might be ok...it's a case of working it out as I go, I guess.
It should be an interesting build...and it'll be different.
Any more ideas/comments, guys?
Rich