'Neato,
Robert Nozick, one of the very important philosophers of the late 20th c., discusses this kind of example in some depth. He considers whether it would be such a bad thing to hook yourself up to an "experience machine", a futuristic device that gives you whatever pleasurable or desirable experiences you'd like. He wonders whether we would really choose such an existence over real life, and argues that we wouldn't. There's a not-bad discussion of the example at Wikipedia:
http://en.wikipedia.org/wiki/The_Experience_Machine, but the original is in his book
Anarchy, State, and Utopia.
BB
