Smal Camera Technologies, which makes image sensors and other components for compact digital cameras, announced Tuesday that Oregon Scientific and Radio Shack are selling credit card-size cameras based on Smal components. Radio Shack's FlatFoto and Oregon's DS6610 both are about a quarter of an inch thick, can capture several dozen images on built-in memory chips, and can use batteries that recharge via the camera's USB (universal serial bus) port. The RadioShack camera sells for $80, while the Oregon Scientific model is priced at $99.