Humm,

I was just at Fry's they have quad Q6600 for 300 bucks with a board and 2G for 50 dollars woth rebate. I passed it up but now I'm wondering, that could make quite a good factoring box with hhh's suggestion.

Considering those quads are droppping to 260 in a few weeks and will overclock to ~3G... I may turn into a Intel fanboy.