Not no-strings free, but still a good deal: The Old Town School of Folk Music is offering two-for-one tickets (normally priced at $75 and up) to its annual benefit show featuring Mavis Staples and Booker T. & the MGs on November 1. (See Renaldo Migaldi's Critic's Choice here). The deal is advertised online as "50% Off Web" but it's also available at the box office.