From now through the end of October, Microsoft is running an "Extended Play Download Days" promotion on Xbox LIVE. What that means: you can save some money on Xbox LIVE's most popular downloadable content.
Major Nelson has the full list of discounted content listed on his blog, so head on over to check out the details on the savings. Some of the content includes Mass Effect's "Bring Down the Sky" expansion (now 300 MS Points), a few Guitar Hero III packs (Foo Fighters, Def Leppard, and the Classic Rock Packs for 360 MS Points a piece), and Oblivion's Shivering Isles (1600 MS Points).
Is there on the list that you've had your eye on for awhile but were too cheap to shell out the points for?