Matt,
I am not trying to be a kill-joy here. My blather represents some things that should be considered.
What will the shipping terms be? Does the donated item get sent to you, shipping paid by donator; or by you? Or paid by the winning bidder?
Have you thought through the time demand factor? Especially multiple concurrent bids - this could become a big chunk of your day.
What is the arbitration process in the event that the recipeint is dissatisfied with what shows up at their doorstep?
Any minimun and/or maximum in terms of value? A brand new 4 dollar mirrolure in the box would be a good buy at $1.30; but is the cut for the site worth the time put into managing the bid process and shipping?
What are the tax implications in terms of liability for you? They could outweigh any fiscal benefit.
The fact I am asking these questions takes all of the fun out of the concept; I understand that. I hope most them fall into the category of my ignorance (which is a very HUGE category

); because I like the concept.
I'll look around to see what I have to donate.
Big Al