Forgotten significance

Do you ever get the feeling that a certain date is important, but you can’t figure out why? You are sure you’re supposed to remember something about it…
4/20 rings a bell. Is it a colleague’s birthday? A friend’s wedding anniversary? Maybe it’s a personal commemoration–my first kiss (but that was at a cast party at university, so it must have been in the winter…) or the start of a new job. It’s not recent; nothing special is noted in the past three years of my weblog.
I just can’t put my finger on it and it’s making me a little crazy this morning.