I'm still mulling this one over. I've been involved in organizing charity auctions in the past (strictly silent) and our chorus has a big auction once a year that brings in most of our funds. It involves a live auction and there's definitely a bit of the bargain-hunting mindset a foot there. I think silent auctions naturally lend themselves to this kind of mentality. The live auction part of our event tends to get a bit more action, but it's kind of late in the evening and not a lot of people seemed to stay last year for that part. I've forwarded Seth's post on to the people in charge of the auction and we shall see what kinds of ideas we can come up with to avoid the bargain thinking.
I wonder, would it still get people in the "giving" mindset if you had the bill signed? Hmm.