In 2007, I carried a Moleskine notebook, an original iPhone with headphones, a Pilot G2 pen, a wallet, keys and a 512MB flash drive.
Today, the flash drive has been replaced with Dropbox, the Moleskine with Field Notes Brand and the original iPhone with an iPhone 4. I’ve ditched the earbuds because I only listen to the iPod while in the car. The wallet and keys are exactly the same (minus Chewbacca), though the wallet contains fewer “Bonus Club” type cards than it used to.
Update: Some others have shared their pockets’ contents, including: