Yes, I've now re listed it to make it visible world wide - I think that the problems with the postal settings on the first listing were entirely self induced and down to my own finger trouble. This new listing is all fine and dandy with hopefully no major errors this time!
http://cgi.ebay.co.uk/Wooden-Orrery-of-the-First-Six-Planets_W0QQitemZ180256733867QQcmdZViewItem?hash=item180256733867&_trkparms=72%3A12%7C39%3A1%7C65%3A12&_trksid=p3286.c0.m14If you're looking for different variations, many old-school orrerys included the Galilean Moons of Jupiter, because they were the first moons discovered beyond our own.
Also, including a high-angle comet might be interesting, but I don't know if it would ruin the aesthetic.
I really like the comet thought, and have toyed with the idea myself for a while, but its a very tricky thing to achieve mechanically. They start farther out than the most distant planet, and eventually get closer to the sun than Mercury, so from a 'lets build it' point of view, I'd have to make it pass through the orbits of all the other planets, without it hitting any of them, or their support arms... Hmm. The only way it could be done is if it moved around
above all the other planets, but that kind of defeats the object I guess. I shall keep thinking about it, 'cause it would certainly look good.
As for Jupiter's moons, there are several Meccano based orreries I have seen that use Jupiter as the central object, and then make the moons the sole subject of the movement. But I think that incorporating this into one of mine would probably be a little difficult.... Static moons anyone?