Staying out late seems to be one of the great pleasures in life... Staying out with someone who's company you're enjoying, and being willing to gloss over what you know you should do and go out for that last cup of hot chocolate or that post-dinner-and-a-movie snack while continuing to realize how much you enjoy their company and just "being" in the moment with them and their presence is worth almost any price.
However, actually dealing with ramifications of the what-you-should-have-done and hearing your alarm go off at 5:30am while having had actually a not-so-great night's sleep (dreaming of the movie you saw and the person you saw it with might sound like fun, and is, until your brain realizes how much fun it's having and wants to directly engage the moment, waking you up to do so) all add up to near accidents on the freeway and nodding off while typing LiveJournal entries at your borrowed desk in the remote office you've had to travel to.
It was fun... but I'm tired. Was it worth it? Last night, yes... at the moment, no... tomorrow, probably. :)