See also: The Myth of Sisyphus by Albert Camus.
Have you read Camus' work? (I have no idea what I expect to hear when I ask this, but:) What do you think about it and about his philosophy in general?
Sorry for the delay, I'd been keeping this comment handy to reply but got side-tracked. I started to read The Plague some years ago and really liked it (despite the unpleasant subject matter), but ended up setting it down for some reason and never got back to it. I'm actually reading The Myth of Sisyphus now, when I can spare a moment to get into it. As for his philosophy generally, I'm afraid I can't say much. Existentialism is interesting overall, but sometimes I think it gets too bogged down in the literary aspects than the practical ones. To me, a philosophy is only useful insofar as it improves once's life. Of course, what "improves" means in this context can itself be a philosophical question. Strangely (or not), I find that as I get older, I'm less interested in things like existentialism (or epistemology more generally), and am spending most of my time thinking about ethics.