Below is a sample (click to enlarge), but you can see all the covers at Tor.com.
These prints are not available for sale. Donated by Tor.com.
Starting Bid: $10.
Bidding starts Saturday, February 11, 2012 at 12:01 a.m. EST (GMT -5) and ends Sunday, February 26, 2012 at 11:59 p.m. EST.