Real-time cloud and vapor sensing technology at astronomical observatories has evolved from eyeballs to CCDs to thermal infrared cameras. In association with the Dark Energy Survey located at the Cerro Tololo InterAmerican Observatory, a "smart" cloud monitor has been developed utilizing an off-the-shelf microbolometer infrared camera and a novel optical design. This system uses several innovative techniques to position RASICAM as the first of the next generation of astronomical cloud monitors, substantially more capable than its predecessors and with genuine science potential. A discussion of the design, algorithms and performance of RASICAM is presented.