David Pogue in the NYT makes a lancing point in a column on home movie downloading:

…Then there is the 24-hour limit. Suppose you typically do not start a movie until 7:30 p.m., after dinner and the homework have been put away. If you do not have time to finish the movie in one sitting, you cannot resume at 7:30 tomorrow night; at that point, the download will have self-destructed.

What would the studios lose by offering a 27-hour rental period? Or three days, or even a week? Nothing. In fact, they’d attract millions more customers. (At the very least, instead of just deleting itself, the movie should say: “Would you like another 24-hour period for an additional $1?”)