One ambitious coder has managed to squeeze Valve's 2008 zombie classic Left 4 Dead into Sony's high-spec PlayStation Vita handheld. It is 100 per cent unofficial, of course, but as the video demonstration shows it's also entirely feasible. Frame rate and graphics appear solid, while the handheld's gyrosensors have been used for smart aiming options.The application could be the first of many homebrew designs that come from the PlayStation Mobile development suite, which essentially opens up the handheld to more indie studios and bedroom coders.