I know they held one in Kansas City, MO this past fall. I'll try and find out what it was from a friend who rode it. He rode it on his 20+year old Trek. He said he almost had the oldest bike there, but one guy beat him by like 5 years.
Maybe you can catch this ride in 2010. Again, I'll do my best to find out for you.
"Things look different from the seat of a bike carrying a sleeping bag with a cold beer tucked inside." ~Jim Malusa
2009 Trek 520-Brooks B-17 Special in Antique Brown
2010 Surly Long Haul Trucker-Brooks B-17 Standard in Black
1983 Fuji Espree Single Speed-Brooks B17 British Racing Green