And in regards to World of Warcraft: I don't regret taking a single character from start all the way to the top levels and following the questlines, and seeing all the lands and so forth. That content entertained me well enough, that I consider it time as well-spent as any other entertainment option.

But I do regret the time I spent on raids and instances, though; which at some point I realized I just wasn't enjoying nearly enough compared to the time I had to waste on them.