Looking for ways to beat the winter blues during another long New England winter? Teams of five to eight people are invited to take part in the fourth annual getfit@mit fitness challenge, presented by MIT Medical. Participants log their exercise minutes into an online database during the 12-week competition. All teams and individuals who meet the exercise goals are eligible to win prizes. Registration opens Jan. 2 and continues until Jan. 23. In addition, an iPod nano is up for grabs in the getfit@mit T-shirt design contest. Visit getfit.mit.edu for more information.