Got out for a 12-miler in the Cleveland Metroparks with a fellow insane rider. About half on pavement, half on snow/ice-packed paths.
Rode the CX rig with some Nokian W106 Hakkapeliitta 35C's. Studs are totally worth it.
Never lost control, but did some rear-wheel drifting on downhill turns. Prettay, prettay cold out.
http://twitpic.com/3okct8