Many museums around the world rent audio players to their visitors to provide automated tours delivering pre-recorded information about their exhibits. Though generally pleased with their patrons' responses to automated audio tours museum administrators find that hosting them can be expensive, time consuming, and frustrating. Ongoing advances in mobile wireless technology provide an alternative to the current cumbersome method of renting sound players to museum visitors. Many patrons bring their own "digital sound player" with them in the guise of their personal cell phone. As cell phones proliferate and the price of calling plans falls cell phones may present a viable alternative to current audio tour systems. History Calls was a recent experiment using VXML technology to deliver an automated audio museum tour directly to patrons' cell phones.