No its not impossible, and no there isn't lag. It depends on what you are willing to spend for a tv tuner. I have a laptop that i used to play my xbox on after i was done basic training. I have an Avermedia UltraTV usb 300 tuner, and man, it plays like a dream. Only thing that is kinda shitty is the output for the sound. I can't seem to get it to play through my laptop speakers so i bought a small set of speakers. BUT before i did own a cheap ass tuner. And there wasn't lag with it either. The only thing was resolution. It seemed the cheaper one would get all pixelated if you put it to full screen. The one i have now can go full screen (17") without any kind of pixelation. Man, its sweet to play on.