Yes. My mother's box she got w/ the gov't coupon lasted about 2 years before dying. I had bought an HDTV for my bedroom a few months before that, so I gave her my converter box.
I am thinking of cutting off my Dish on my LR TV (tube type), so now I will have to buy a new box. Last time I checked, you could get one for 40-50 bucks. If they're more than taht now, I may just splurge and replace the TV instead.