I know it's extremely geeky, but in my journal I use the number of days since I was born as a kind of "stardate". For example today (for me) is day 10872. I'm 29, it's been a little over ten thousand days since I was born, and I figure I've got at least another ten thousand or so barring some unforeseen accident or illness.<p>Seemed kind of pointless to do this at first, but this "numbering convention" stuck with me because it lets me keep in my mind the idea that I _do_ have a limited number of days left on this earth -- and I'd better make the most of them!