When I was shopping for a TV at best buy, I noticed that some of the small TVs actually ran off of 12V DC. The included power supply simply converted the household AC to 12V DC. If you are near a best buy, it might be worth seeing what they have. I cut off the TV side of the cable, spliced on more wire and ran it to my house battery fuse box.
Keep an eye on the amperage draw of some TV's. Right now I'm just using a DVD player but have been looking at a larger flat screen. Road Trucker deals with a lot of 12v TV's and although a retailer, their opinions are worth a read: RoadTrucker : Product Info
I'd rather have a 12v TV than running my inverter or even a small inverter sized to the TV's load. That just fits better in my situation.
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