If you’re in the mood for something a little unusual tonight, you’re in luck. In celebration of the opening weekend of their new visual music exhibit, the Hirshhorn museum will be open from 9:30 p.m. until 2 a.m. The exhibit explores “the many forms of visual music, an interdisciplinary, broad-based art movement that explored the relationship of abstraction, color, and music.” Their online exhibit has more photos and information about the paintings, film, and installation…