How many yellow Bob Jacksons are out there?

Momentum My point is that it's slightly galling when someone gets a good deal on the basis that they're a fellow cyclist, member of a forum etc and then sells it for profit.

Yep, I agree with that. It's different to what I was thinking about though - I see no problem buying from Random1 selling to Random2 at whatever profit you can get.

I would expect though, that if someone gave me a sob story about, say, a broken Flite saddle and I gave them my spare one, it wouldn't end up on ebay 2 days later.