It's all happening in Vegas at the Consumer Electronics Show. Big 4K screens, big smartphones and, er, a teeny wearable computer mouse that slips over the finger? Yup, that'll be the Genius Ring Presenter then.What may at first sound rather bonkers does have its practical use. Think about a presentation where you want to "play the weatherman" and navigate around screens when in front of an audience, for example. Well now you can, but without wires.The Genius Ring Presenter, as the name suggests, is more than just a mouse though. There's also a built-in laser pointer to assist with those presentations. Or just to shine in people's eyes to cause a nuisance.The wireless mouse has a variety of buttons to adjust the mode of operation, as well as left and right clicks as on most standard computer mice.But it's a short-lived charge capable of only about 10 minutes of laser pen pointing and scrolling action before it needs to be plugged in again to juice back up.It's all here at CES. The good, the bad and the borderline crazy.