What's Your Four Twenty, Partner?

Lynn and I are watching last week's SNL, and there's a bit about a secret agent named 420--of course, he's a stoner. I had just learned about this bit of slang not that long ago, and Lynn had never heard of it.She said, You're from Eugene. If you've never heard of it, how much of a term for marijuana is it? I said, "In Eugene, we called marijuana 'marijuana.'" Then we laughed for 3 minutes.