You're probably thinking, "Why the hell does this guy have a BNSF page in the Massachusetts section of his website?" Because between July 23 and July 30, 2004, ten of BNSF's business cars were parked at Boston's North Station for the Democratic National Convention. The cars were brought in behind Amtrak's Lake Shore Limited in two groups on July 21 and 22, and were moved to North Station on the evening of the 23rd, having spent most of that day parked at Boston Engine Terminal. Very early on July 30 they were moved from North Station to South Station, where they were coupled behind the westbound Lake Shore Limited. I was able to photograph several of them before the train's 11:45 AM departure.
 

Here's the list of cars:

BNSF 32, William Barstow Strong, theatre/lounge/inspection car (ex-Atchison, Topeka & Santa Fe)
BNSF 28, Mountain View, lounge car (ex-Great Northern)
BNSF 10, Lake Superior, dining car (ex-Northern Pacific)
BNSF 11, Fred Harvey, dining car (ex-AT&SF)
BNSF 29, Valley View, club lounge car (ex-AT&SF)
BNSF 2, Columbia River, business car (sleeper) (ex SOO, ex-GN)
BNSF 67, Trinchera Pass, sleeper (ex-AT&SF)
BNSF 64, Marias Pass, sleeper (ex-AT&SF)
BNSF 1, Mississippi River, observation car (ex-Chicago, Burlington & Quincy?)
 
Norfolk Southern also sent its business cars up for the DNC, but I was unable to get any photos of them.