Another day, another hair color! Mercurial singer Katy Perry may have been trying to hid her head under a beanie, but we couldn't help notice her newly red tresses -- and of course we dig the punky new style!

Flanked by one big security guard, the "Dark Horse" songstress was at the LAX airport wearing a plaid minidress, tights, combat boots and a leather motorcycle jacket. That's one sexy lady!

The "Hot and Cold" singer turns 29 later this week. Last week Katy tweeted that all she wanted was her name on the marquee of a Shakey's Pizza Parlor in Los Angeles. Ask and ye shall receive, KP! On Monday morning, the pizza palace put up a "Happy Birthday, Katy Perry" sign, and then a rep said the chain restaurant was planning on changing the marquees on all their California locations for the fun-loving birthday babe. That's what we call a California girl!

Apparently Shakey's also wants to name a pizza after Katy, and throw her a bday bash. Umm can we come?!