How about just over 3 days?
"Tesla Motors Team Completes 76-Hour, Cross-Country Trip"
http://www.pcmag.com/article2/0,2817,2430243,00.asp
What you guys aren't factoring in is the Taxes that will be added as more of us adopt electric car tech. Also the charging price will go up as gov't subsidies are reduced. Will ultimately cost the same or more as everyone pays now. You know it's true.
Cross Country in 76 hours? That's not so fast. I went from California to Maryland in about 4 days in my Truck while pulling a loaded trailer and doing 65 mph MAX. (try THAT with yer little expensive go-cart)