Grab bag sales are like old-fashioned box auctions where bidders aren't allowed to see items until they've purchased them. They appeal to the treasure hunter in all of us. Grab bags are like Christmas stockings. You never know if you'll get an orange or a lump of coal. For your grab bag event, include a few nice items in the mix. There won't be a great gift in every bag, but some bags will be well worth the flat rate purchase price. Internet sites like Woot.com offer their own versions of the grab bag concept on a regular basis very successfully.