Well girls and boys, if you're in San Francisco, today's your lucky day! It looks like Sprint has finally switched on its WiMAX 4G network in the city by the bay, so whip out your Sprint Overdrive, EVO 4G, or Epic 4G and join the party. We've tested connection speeds using the Epic 4G in Potrero Hill and are seeing between 5 and 7 (!) Mbps down and 1.2 Mbps up with 6 full bars of signal indoors. Even after moving 4 blocks away, download speeds stayed between 2 and 4 Mbps, with the signal dropping to 4 bars, so it appears we've finally reached the realm of "ludicrous speed" on mobile devices. Hit us up in the comments and let us know what kind of performance you are seeing, and in what neighborhood you're located.