OK, these people aren't really your new BFFs, but that doesn't stop the masses from coming together at Rillito River Park on a weeknight in early September to witness the nightly swarming of the Campbell Avenue bridge's resident bat colony. The atmosphere is decidedly festive, with bat-speakers, bat-music and an array of batty performance artists. And don't forget the goofy teaser signs strung out along Campbell Avenue. If you are, in fact, looking for a new BFF (or something more), you can always share your knowledge of bat culture—like, for example, how bats will each devour two tons of insects throughout the course of their seasonal stay. How's that for a conversation-starter?