Birge Hall isn't really a place you'll end up in much unless you really have a yearning for hot physics action. There isn't much else of a reason to cross from LeConte, unless to pester your GSIs (and fail) to get points back on your problem set mishaps. There is a rumor that Oppenheimer's communist records are stored down here. Who knows.
For those of you who have no idea what's going on here, Birge Hall is that squatty little thing right to the near east side of the Campanile. You know how there's always this hot chick you want to go home with at the bars, but there's always her shrill, uninteresting, insensitive friend trying to block your way? She's Birge. You're trying to get to the Campanile in all circumstances. Ignore Birge.