The following post was sponsored by Sitbetter.com. Our sponsors are hand-picked by the Design Milk team because they represent the best in design.

Sitbetter.com is giving away one of three brand new chairs in the “Tell Us Why You’d Be Thankful for a New Chair” contest. One lucky winner will get to choose one of three different chair options.

Sitbetter wants to hear why you’d be thankful for a new chair in 200 words or less. Special consideration will be given for those that upload videos or upload images. The Sitbetter contest is a nationwide contest (excluding Hawaii and Alaska) that is part of their bimonthly contest series promoting healthier chair options for anyone and everyone.

The contest opens today, November 2, 2009, at 8:00 a.m. PST and closes on November 23, 2009 at 11:59p.m. PST. The Sitbetter “Tell Us Why You’d Be Thankful for a New Chair” contest is open to legal residents of the United States, age 18 and older. They want to hear why you would want a new chair, what problems you are having with your current office chair, and how you could benefit from a healthier chair option. The prizes to choose between are either the Posture Perfect Evolution Exercise Ball Chair (retail value $159) the Kore Ergonomic Rocking Stool (retail value $99), or the Office Star Ergonomic Knee Sit Chair with Dual Knee Pads (retail value $89). The winner will be announced on December 1, 2009.

Enter now at Sitbetter.com.