Consider going to Capitol Hill and dropping in on the Senate during its marathon sessions in the frantic few days before it takes its Christmas break.
During normal tourist times in Washington, getting into the Congressional galleries can be a huge pain. You wait in long lines, you're ushered in and out for a relatively short stay, you're amid busfuls of visiting tour groups, and unless you happen to be in one of those visiting groups, on the whole it's better just to watch things on C-Span if you follow them at all.
But two days ago, on a very cold Sunday in DC (Potomac frozen bank-to-bank by the Kennedy Center in December -- not a usual sight), my wife and I were on the Mall with our two visiting sons, thawing out in the always-wonderful US Botanic Gardens Conservatory. By chance we ran into friends we'd known in Beijing, one American and two Chinese. They said that they had come straight from the Capitol, where they'd been sitting listening to a debate about the new START treaty. "The doorkeepers thanked us for coming," one of our friends said, "We were the only ones there."
Hmmm! We walked up Capitol Hill, descended into the huge underground maw of the new Visitors Center, and after passing two security checkpoints (metal detectors; but no shoes-off or pat-downs) we came into the Senate gallery just as a vote on a START amendment was taking place. There were far more Senators on the floor than civilians in the gallery -- it was one of those rare moments when nearly all the Senators show up to vote, overseen by the unblinking C-Span cameras and a crowd of maybe 20 or 30 civilian spectators.