Eight Celebs Go Undercover

Daniel Radcliffe's disguise couldn't keep fans from snapping photos of him.

Sept. 6, 2009 — -- When you're a celebrity, staying incognito is key. Best way to achieve said results? Disguises. Just ask Joaquin Phoenix.

Daniel Radcliffe and Rupert Grint attended the Reading Festival in the U.K. and took a tip from his playbook by showing up in some oh-so-inconspicuous matching helmets and goggles. Of course, no one noticed them at all as they rocked out to the punk band Gallows. Below, check out some other great celebrity disguises guaranteed to promote attention ... and sometimes anonymity.

Either Prince Harry is really feeling the '70s, or this is a bad disguise. [Click HERE to see the photo.]

Is that Lily Tomlin? No silly, it's Heather Mills. More importantly, is she starting a "disguise line" along with her eco-friendly line? [Click HERE to see the photo.]