With one-touch access to any phone number at any time on our cellphones, Google, and all our GTD lists getting stuff off our mind, what pieces of information are important enough to commit to memory? The Cranking Widgets blog lists eight numbers you "should've memorized a long time ago," from your social security number (yes), to your debit card number (really?) to your licence plate number (uh-huh) to your phone number (of course!). I don't know my car insurance policy number by heart or my checking account number, but my ATM card PIN and super high-security master password live only in my brain. What numbers do you commit to memory? Let us know in the comments.