Stop by the Prudential Center today at the Boylston Arcade entrance for a free slice of pie. The nonprofit Community Servings is having their “Pie in the Sky”rel=”nofollow” (and serving free slices). Buy a pie for $25 and you’ll sponsor home delivery of food to someone with a critical illness for a week. Pies can be picked up Nov. 24 at 45 locations throughout Boston. Every year more than 150 bakers donate pies to this cause.