othing gets you through the midweek blues like the playful sound of a banjo. Every Tuesday the best bluegrass pickers from near and far come together at the Cantab Lounge to sip Bourbon and jam in the spirit of Bill Monroe. But even though the Cantab is known for its open-mic nights, Tuesday remains an in-the-know thing. Before the feature band takes the stage at 10, musicians pick and strum together just about anywhere in the place they can find room. Not a bluegrass fanatic? Come with your mind and ears open and by the end of the night you’ll be enthusiastically throwing your cash into the donation hat. (There’s no cover charge.) Here’s a tip: Get there before 8 and snag a seat in front of the upstairs stage to avoid making friends with the back wall. If it’s still too crowded for you, there’s a full bar in the basement, complete with dusty bottles of liquor and barstools that look like they predate the bluegrass movement. Wallace