Now that the 2011 Nationals test has been revealed, I can share my Waco RPT photo shoot. The RPT competed for a US military contract in the early 1940s and lost. The sole example was originally built with an open cockpit. A later owner added the canopy. The aircraft has only 85 hours total time and has rarely ventured out of a hangar. It is currently offered for sale on Controller.com for $57,900.
Prior to spring of 2011, only one or two photos of the RPT existed on the web. This was one of them, shot at Oshkosh sometime in the 1970s or 1980s:
After tracking down the owner, I managed to get permission to do a full photo shoot. It can be seen here.