[Update] Hugh Stimson in the comments points out the things that Woz carries in his backpack that aren’t in the photo:
the AirPort Express and MacBook Pro 85W magsafe adapter, which are out of sight in this photo,• bluetooth mouse,• binoculars,• projector connectors,• multiple Gameboy Lights (a Gameboy sold in Japan but never in the U.S.),• Gameboy link cables,• plenty of foreign AC adapters,• prism glasses for watching movies in bed,• sunglasses,• earplugs for concerts,• Ultimate Ears UE18 earplugs for flights,• Gameboy link cable,• tons of pencils for pencil games on flights,• tons of pens,• tons of sharpies,• tons of paint pens (signing),• red-blue-purple-yellow-green laser pointers,• credit cards,• hotel cards,• airline cards,• hard rock card,• medical cards,• small accessories like olloclip iPhone lens adapter,• Square,• flash keys,• flash media adapters,• cigarette lighter dual USB adapter,• audio doubler cable,• iPad USB/SD Card adapters,• toiletries for hotels,• batteries of many types (AA, AAA, CR2, CR128, odder types for things like my bag beeper for locating my suitcase)• eyedrops,• $2 bill pads,• pencil puzzles,• itineraries for upcoming travel…