The official name for it is “gesture-recognition technology,” but no self-respecting geek would call the process of poking your finger at a computer screen anything but “touchy-feely computing.”The tablet PC, which uses this kind of interface, has been around for a few unremarkable years now, as have those cash registers one sees in sports bars and some restaurants. There was a desktop computer model made by Hewlett-Packard Co. in 1983, called the HP 150, which was one of the first touch-screen machines. Interest in the touch-screen interface has bubbled up again; Apple introduced the iPhone a couple of weeks ago, dumping the slender stylus in favour of the fleshy fingertip; in late May, Microsoft announced that in the fall it will release Surface, basically a