Current contents of my bag (which is a SwissGear backpack - one of the ones sized for 15" laptops)

Laptop: Dell Latitude D620 (cleverly disguised with Apple logo covering Dell )

Gadget bag (Eagle Creek Quarter Cube):
* Sierra Wireless AirCard
* iPhone USB charger and USB-Dock cable
* iGo DualPower dongle with y connector for iPhone and Samsung
* Samsung external battery charger (for my Blackjack)
* a USB extension cable
* Presentation remote + USB dongle + spare battery

Loose in the main compartment of the bag:
* iGo 130W air/auto/plane adapter
* WD 250GB hard drive
* D-Link travel wireless router
* 3-outlet grounded splitter (to butt into an occupied outlet at the airport)
* External Li-Ion pack to recharge/power iPhone on long trips
* Flip digital video camera
* REI therma-rest style inflatable seat cushion (to make those coach seats a little more comfy)

Main compartment still has space for a couple of notepads, clipboard, snack, and 2-3 paperbacks, while still fitting an RJ overhead bin.

In the gadget pocket up top
* A couple of USB thumbdrives
* Shure SE530 earphones with iPhone cable (adds an inline mic)
* Extra foam tips for Shure
* Regular earplugs (Etymotic tri-flange reusable)
* Jawbone and USB charging cable

* iPhone in my pocket