Today I bring you a story that has it all: a solar-powered, low-cost, open source cellular network that's revolutionizing coverage in underprivileged and off-grid spots. It usesVoIP yet works with existing cell phones. It has pedigreed founders. Best of all, it is part of the sex, drugs and art collectively known as Burning Man. Where do you want me to begin?"We make GSM look like a wireless access point. We make it that simple," describes one of the project's three founders, Glenn Edens.The technology starts with the "they-said-it-couldn't-be-done" open source software, OpenBTS. OpenBTS is built on Linux and distributed via the AGPLv3 license. When used with a software-defined radio such as the Universal Software Radio Peripheral (USRP), it presents a GSM air interface ("Um") to any standard GSM cell phone, with no modification whatsoever required of the phone. It uses open source Asterisk VoIP software as the PBX to connect calls, though it can be used with other soft switches, too. (More stats in a minute that I promise will blow away your inner network engineer.)