If you were wondering just what that extra dollar buys you when you upgrade to HD in the iTunes store, you can get a free look. Our pals over at TUAW made note of a number of shows that have free episodes available, in HD. The files are large, with the HD versions clocking in at right around 1.5GB, so it will take a bit to download. Something that isn't helped by the fact that iTunes downloads the SD version as well.

I've been taking a look at them and I grabbed screenshots from Heroes, Life, and Battlestar Galactica to give you an idea of the difference in the picture. It's fairly dramatic. Those captures, and the full list of free episodes, with the iTunes links, are after the jump.