The Daily Grind: How late is too late?

We know how it is. You get into a good group, the experience and loot start flowing freely, and before you know it, it's oh-dark-thirty. Sometimes the gaming groove is too good, and you just can't tear yourself away. For that matter, if there weren't enough of us doing this, the phrase "just one more level" wouldn't be quite so funny. For today's question, we'd like to ask you just how late is too late for you? Is there such a thing as "too late" in your life? Or are you one of the folks who have those real-life responsibilities and who turn into a pumpkin if you stay up past midnight? (Whatever you do, don't get busted napping at work after pulling a gaming all-nighter, lest someone put a picture of you out on the 'net!)