Grab Sonic the Hedgehog (Xbox 360) for $19.99.  It is the Amazon Deal of the Day for Monday, June 18, 2007.

Grab some a Microsoft Points card to get you order over $25 for free shipping.

Check it out:  Amazon Deal of the Day 

Product Description
Sonic The Hedgehog, the Sega classic that changed the way games are played, has come to the Xbox 360 with exciting new features! For the first time, you'll be able to save your high scores and progress as you rocket through the seven gravity-defying stages that started it all. After you outrun Dr. Robotnik and his badniks in Original Mode, race through the famous loop-de-loops even faster with Sonic's trademark Spin Dash in Anniversary Mode which celebrates Sonic's 15th birthday. This special 15th Anniversary Edition also brings tunes from the original soundtrack which you can unlock as you finish the stages.