An application that is downloaded from the Web each time it is run. The advantage is that the application can be run from any computer, and the software is routinely upgraded and maintained by the hosting organization rather than each individual user.
Traditional contests print a set number of ballots, allowing odds to be determined.
Still, contests and sweepstakes are popping up all over the Internet. The latter kind is becoming more popular with retailers such as La Senza and with their customers. They don't think the contests are terribly commercial. Contests are nice things. They're part of having a quite pleasant visit.