I haven’t vetted the analysis, but no doubt this is the slickest looking carbon calculator I’ve seen yet! (From EcoSynergy; nice job!)

(Also just stumbled across this more ordinary looking but not at all dumb household GHG calculator from EPA — simple but usefully interactive. And then there’s my slowly accreting (it’s impossible to keep up!) Carbon Calcuators compendium over on Squidoo. (Go on over and add some!)