A scruffy, dim, and not terribly clean addition to the repertoire of live music bars in San Francisco, the Elbo Room might be the sort of place to avoid, if it weren’t for the terrific daily lineup of live music. Downstairs is a bar, nothing fancy, but popular. Upstairs is live music just about every night of the week. The music at the Elbo Room varies from acid jazz to electronica to indie rock to Afrofunk to Latin rock-anything likely to appeal to the musically omnivorous post-collegiate city kids that throng the place. Thirty-somethings and even open-minded forty-somethings can throw on their favorite pair of Diesel jeans, the latest retro Pumas, and a smartass T-shirt to taste what the younger generation is listening to these days.