If you've been passing on H.264 encoding for your iPod or Apple TV because of speed, Elgato's Turbo.264 ($100) is here to help. As a Mac-compatible version of the ADS Tech Instant Video To-Go USB dongle we've previously reviewed for PCs, Turbo.264 is designed to accelerate high-quality H.264 video compression to roughly five times original speeds. It comes with its own attractively designed, simple video transcoding software, and automatically increases…