1. fake-obese Ben Stiller singing Kelis's "Milkshake" = end credits of Dodgeball: A True Underdog Story (2004)
2. fake-obese Eddie Murphy, as a woman, singing the Pussycat Dolls' "Don't Cha" = trailer for Norbit (2007)
3. chubby Kyle Gass singing "Don't Cha" = TV ad for Wild Hogs (2007)
4. husky Will Ferrell singing the Black Eyed Peas' "My Humps" = TV ad for Blades of Glory (2007)
Conclusion: laughs may increase in relation to actor's girth, prosthetic or otherwise; actor can be black or in drag, but whiteness of actor increases intended hilarity of hip-hop song being performed poorly.
Am I missing any movies from '05 or '06, or before '04? Let me know.