The Cal Academy of Sciences hosted their first "Nightlife" event, on Darwin's 200th birthday. The museum was transformed into a club-y atmosphere, mostly via the DJ music played via loudspeakers throughout the space. One has to wonder what the live animals think of that. For 21 and up only, it was nice to visit the museum without the masses of children and strollers. I was event photographing, and everyone was in very good spirits, which made my job easy.
There was some special programming - a constellation show in the planetarium, a speaker (about Darwin, most likely), and each of the departments (Ornithology, Herpetology etc) had an interactive table where people can speak with researchers and look at specimens in the collection. All that, plus the music and drinks and lack of kids, were the differences from a day time visit. I think I've been going to CAS too much recently, and am starting to take it for granted... I want to see something different there. I'm going again tomorrow... 4th time this week.