On a small scale, it would be a nice resource for the members of this list to have a simple, searchable registry of who's looking for what. You don't even have to disclose what you're willing to pay (I think it'd be much more anti-ebay if there weren't any dollar signs on it at all), but just that you would like anyone who has one of these systems available to contact you. This would simply be a contact facilitator, and the independent parties could then negotiate prices, etc. Worst case would be that the professional auction sellers would find out and start flooding the registrants with URLs of their eBay auctions. But if it's a "registered user" service, it would be simple enough to implement a "no-eBay" policy and boot people for doing that.