Backstage Auctions currently have a 'Rock & Roll Summer Classic' auction underway which has no less than 210 lots dedicated to KISS.

Among the items are hand-written lyrics to 'World Without Heroes', items from the estates of Peter Criss and Eric Carr, never-before-seen photos, an exceptionally rare 'Rock 'n Roll All Night' acetate and several unique recording reels.

The full list of items can be found here: http://www.backstageauctions.com/catalog/kiss/ac/0/765/

Also, there's a blog written specifically about the KISS contents in the auction.