In my "side job" (tech support/consultant – which was my full-time gig before coming to take over the family sign business), I was fortunate enough to have a customer gift me a 40-inch 1080p LED TV, which was a bit too banged-up for me to use as a TV, but just perfect for use as a main display at the shop. Comes in really handy when having to show designs to others (customers, coworkers, etc.) in the room. I have it set up as my main display, with a smaller 19-inch display also connected as an extra monitor for things like tools, palettes, etc.
Honestly, though...most flat-screen TVs are very affordable these days (especially 40-inch & under), and as long as they have a HDMI-in port, you can get an adapter to use them as secondary (or even primary) displays on most computers, if you could use the size and/or real estate.