Joaquin Phoenix went on Letterman Wednesday night, ostensibly to promote his new movie Two Lovers, but it was his combative, monosyllabic appearance that made news. The Walk the Line actor seemed to get perturbed that the audience didn't take his hip-hop career seriously, just about got in a fight with Paul Shaffer, and stuck his gum to Dave's desk, in addition to being all shades-and-beardy. Honestly, I try to reserve my Riff postings for actual, somewhat serious arts and culture news (and French techno tunes I think are awesome), but this really must be seen to be believed. Is he doing a shoot-the-moon, Andy Kaufman bit, or is he just trying to burn up his feathers and nest so he can emerge anew? Only time, and the new J-Pho album, will tell.