If you hook a 'TV' up to a sat box, then you are using your TV as a monitor... That's all projectors are (typically), monitors.
So, yes, I am sure others use their 'work' projectors for home use. But, most home enthusiasts buy projectors for home use and then build nice rooms around them. Home theaters are not necessarily very expensive and decent setups can be done with 5.1+ surround and a 8 foot screen for under $2,000.00. Far less than say, your average rear projection screen setup and about the same as some of the cheap 42" plasmas.
Oh - and yes, you hook up your cable box, satellite, X-Box, VCR, and DVD player. Watch HDTV programming and have an incredible experience all around. Lots of very good info on projectors at
www.projectorcentral.com