Get a one year membership to the Museum of Contemporary Art for almost half-off, with a choice of Household or Friend plans.  Household gives you all the following benefits, while the Friend plan provides more:

Invitations to all Members’ Previews of major exhibitions
Invitation to shop during members’ double discount days
Up to 20% off tickets to MCA performances and lectures
10% discount at the MCA Store and MCA café
$4 discount on parking
Discounted admission to First Fridays
Subscription to Dwell Magazine

It’s usually much cheaper to buy an annual membership even if you’re only going to visit once or twice.