There are some composite-to-HDMI converters available. I have no idea how well they work, in terms of image quality and lag. (The processing needed to convert the analog video signal to digital, de-interlace it, and upscale it to HD resolution can cause a delay, and if that delay is long enough, it can cause fast-action games to become unplayable. Even a lag of only 1/10th of a second can throw off your coordination and make the game more difficult to play.)