If you're looking to get rid of your cable or never had it to begin with, the Homeworx HDTV Antenna is the cheapest way to get free, crystal clear over the air HD on your television.
At under ten dollars, the price more than makes up for the occasional hiccup. The antenna's base does a decent job of sticking to surfaces, although you won't want to stress it too much. If you live in a city you likely have a decent broadcast source, like San Francisco's Sutro Tower. Getting high definition major networks and a selection of local favorites for free makes cord-cutting an even simpler proposition.