The ADDeRebbetzin, as I've noted before, teaches at a few American post-HS seminaries. At one, they held an auction for tzedakah. Each teacher autioned off a service of some sort, and the students bid (real money) on the service, with the proceeds going to tzedakah. The Rebbetzin did ok - she auctioned off a movie night, maximum 2 students, at our home. It went for 200 NIS. The most expensive item was bought for 1000 NIS by 4 girls. It was a trip to get a bracha for shidduchim from R' Scheinberg.
Words fail me.