The Wisconsin State govenment has passed a law taxing digital downloads:
The State of Wisconsin has passed legislation to extend sales tax to digital downloads. The new law will go into effect on October 1st. Estimates suggest that the 5% tax on “downloads of music, games, books, ring tones and other video entertainment” will bring in $6.7 million annually. “[Wisconsin Governor Jim Doyle] has been fighting for the change for years. He and other state officials say it is a matter of fairness: Internet vendors shouldn’t have a tax-exempt advantage over Wisconsin’s brick-and-mortar retail stores.” Similar legislation has been proposed in North Carolina, and we’ve previously discussed New York’s foray into taxing sales made online in addition to downloaded purchases.
Good luck taxing BitTorrent downloads :-)