You often can get the Houdini at the Patagonia Outlet stores for about 40% off; also check Sierra Trading Post every once in a while.

My main criterion for a wind shirt is breathability. It needs to stop the wind, but not be coated to stop rain, etc. It's one of my most worn pieces of clothing (on the trail) from Sept. through April or so. For a while I used a Mountain Hardwear pullover, but recently I've liked a pullover wind shirt from -- wait for it -- LL Bean. It was <$20 at their outlet, and works quite well.