Paul Graham also has an essay which explores the same core idea, but imho he manages to explore more angles of the passage of time, and how we perceive it through the scarcity of different experiences we value. If you liked this one, check it out:
Man this was hard to read. My parents moved across the country a few years ago, went from seeing them every two weeks to twice a year. I'll be lucky to see them more than a couple dozen times total for the rest of our lives.
http://www.paulgraham.com/vb.html