Britney Gives K-Fed a Happy Birthday

Britney Spears and hubby Kevin Federline celebrated K-Fed's birthday Tuesday night at Tao Restaurant in Las Vegas. TMZ obtained this video, showing the craziness surrounding the latest Britney sighting.

There were eight -- count them, eight -- security guards at the ready as the couple went out on the town.

For the record, Federline is now 28.