For actors, there's nude. And then there's NUDE. As in buck nekkid. As in my-mother-can't-see-this! nude. Just ask Michelle Williams. The naked truth is, the "Dawson's Creek" bad girl struts onstage in her birthday suit in the Off-Broadway show "Killer Joe" every night. All in the name of art. But when the men's magazine Maxim wanted her to reshoot a sizzling cover, Williams balked, saying she "felt like a piece of meat." Williams says she almost wept over the sexy poses. "It was about getting me into the tightest, shortest, most provocative thing they could find," she tells Paper mag. Nooooo! In a men's mag? Shocking. Williams insists she has no problem displaying her body issues to the world. "I don't live up to what I see in the magazines," she says. "I'm never going to be (model) Amber Valletta. The odds are I should be milking a cow right now." Every starlet's dream, no doubt. But what's the difference between her posing in Paper mag in a spangled bikini and posing on the Maxim cover in a skimpy red number with one strap off her shoulder as she gazes seductively into the camera... or is that what they're wearin' to milk cows these days??