This is the droid you're looking for. Congrats to the eagle-eyed fan who won the Star Trek Easter Egg Sweepstakes by spotting rival franchise robot star R2-D2 in a blink-and-you'll-miss-it moment in the new Trek movie.
The contest, announced with some fanfare on Star Trek's Facebook page last month, has a winner: Scott H. of Erie, Colo. who writes:
During the Drill Machine sequence as the Enterprise comes out of its barrel role amidst destruction of the other Federation ships above Vulcan, we cut to an interior Enterprise bridge over the shoulder of Kirk that is looking out through the front viewscreen. In space, R2-D2 is floating in the debris from about the top middle of the screen to the bottom right.
For his prowess at spotting Star Wars droids infiltrating enemy territory by disguising themselves as garbage, Scott H. wins a prop phaser from the movie (retail value: $100, unless Scott puts it up on eBay). No prize for spotting any of the film's other Easter eggs, in-jokes, stunt-casting cameos, or references to other works, but TrekMovie.com has a pretty comprehensive list of them.