Running a contest on Twitter? Picking a random Twitter friend as a winner of a contest you run on Twitter is super easy with TwitRand. To use TwitRand, simple enter a Twitter username and choose if you want to pick a random winner from your Friends or Followers.
TwitRand will then use a script to pick a completely random user from your desired group as the contest winner. You can also use TwitRand to pick a random person from group of people who have ReTweeted the same thing. To use that option simple enter the URL or phrase and TwitRand randomly pick one of the ReTweeters as the winner. However, the number of ReTweeters must not be more than 1,500 people for this option to work.
It is a simple tool that does not require any download or registration and takes less than 30 seconds to pick up a random winner.