*Strike up the droids: This whimsical painting by artist John Alvin (front) shows C-3PO and R2-D2 as virtual one-droid bands. Lore has it that the art was commissioned for a concert tour that was cancelled(sic) after only one performance, and that the finished poster (back) was sold only one night at the Hollywood Bowl. This is perhaps the most sought-after trilogy poster, with authentic copies fetching more than $1,000. *Source: Back of card