The online trailer for The Signal, a low-fi horror flick releasing February 22 from Magnolia Pictures, is an effective piece of genre rib-nudging. Like Pulse and the recent One Missed Call (and The Ring, before them), The Signal is a film that channels and wraps the current anxiety of our times around a techno-phobic premise. When a garbled television transmission makes half of all those who see it turn into stark-raving-mad killers, all bets are off. Like the recent Cloverfield, the movie seems to revolve around a couple of young lovers trying to navigate their way through the madness and reunite safely. It may not have the marketing muscle to punch through, and heck, it may even be crappy in the final analysis, but the trailer does its job, evoking dread in decently effective fashion.