If you work in front of a computer, you should buy an office chair. But for some reason, some home office workers refuse to cave and buy one. Whether it's price, size-constraints or commitment, we understand if buying an office chair isn't in the cards. The least you can do is buy a seat cushion. Not one of those decorative, unsupportive slabs of foam, but rather an ergonomic accessory that will improve your posture and productivity. None of these seat cushions will make your dining chair into an ergonomic throne like one from Knoll or Herman Miller, but they will make your 9-to-5 seating situation just a little better.