Sight, the workhorse of the five senses, puts in too many hours keeping man from falling in manholes. Reward the most overworked sense with today's Groupon: for $40, you get a one-year individual membership to Carnegie Museums of Pittsburgh and a $5 gift card to museum cafés (an $80 total value). This Groupon also includes a $10 museum-store coupon for purchases more than $25. The museum membership must be activated by January 1, 2012.

Carnegie Museums of Pittsburgh corrals four of the city's finest institutions, including the Andy Warhol Museum, Carnegie Science Center, Carnegie Museum of Art, and Carnegie Museum of Natural History. Members receive one year's worth of unlimited general admission to each Carnegie museum in addition to invitations to members-only exhibition previews and art heists. A subscription to the quarterly Carnegie magazine keeps members abreast of comings-and-goings at the museums and proffers in-depth discussions of current exhibitions. Inquiring noggins remain nourished with chewy tidbits of knowledge plucked from discounted classes, camps, and IMAX films. Those who like to travel can also get free admission privileges to more than 300 participating science museums throughout the nation, affording road trippers the chance to see the California Science Center or the Museum of Einstein's Mustache Combs. Redeem this Groupon by December 14 to ensure timely, pre-Christmas delivery.