If you are in the market for a new stereo receiver most of the new ones have component connections. This is what I am going to do once I am out of school.
The cheapest way to go is to buy a RCA Y splitter (1 male, 2 female) and hook them up that way. I currently do this because I am the only person that uses my TV so I know that nobody will have more than one device on at once. If more than one person uses the TV I would not recommend this solutions.
The next cheap solution that I know of are the component switches that are geared toward gamers. I remember seeing one at Best Buy that was $20 and had 4 inputs. The switches geared toward the Home Theater market are much more expensive.