Calzaghe had the brains to hit and run...utilize his jab and stay out of harms way to win a decision vs Tiger. That's the way that anybody with brains would fight the Tiger-man.
I love Tiger but Calzaghe's speed (both hand and foot) make him a tough out. Tiger was at his best with guys that stood in front of him. Calzaghe liked to flurry with his amazing hand speed and get out. I would favor Joe by UD.
Another vote for Calzaghe. Tiger was very tough so I doubt zaggers could get him out of there. Tiger also had a heavy punch but it was relatively slow especially when compared to a speedster like Joe. I think Calzaghe flurries, sticks and moves all night long and makes Tiger look worse than he actually is.