When I travel I go carry on only. I have one plane sized carry on bag for clothing. I have a backpack for the computer, etc. that qualifies as my “purse” or “handbag” for carry on even though it is quite roomy. Here’s the backpack I have for the computer: SOLO Sterling Collection Laptop Backpack, CheckFast Airport Security-Friendly, Holds Notebook Computer up to 16 Inches, Black, CLA703-4 You can also find this or similar items at Office Max or Office Depot for a decent price.
I carry lots of extras to be prepared:
POWER
Apple Power Adapter (comes with your laptop)
Power Strip or Splitter – Monster Outlets To Go 4 Outlet Travel Power Strip
3 Prong to 2 prong grounding converter
For international travel… World Travel Adapter Plug Set
OTHER
Display adapter for laptop to VGA (for projector connection)…depends on your laptop model.
Black RJ45 Computer Networking Cat5e Ethernet Patch Cable – (3 Feet)
STORAGE and BACKUP
USB Flash Drive…formatted as Windows drive to transfer files between any computer. SanDisk Cruzer 8 GB USB 2.0 Flash Drive
External bootable hard drive with full backup using SuperDuper. LaCie Rugged All-Terrain 500 GB FireWire 800/ FireWire 400/USB 2.0 Portable External Hard Drive
Other World Computing also makes great portable drives.
To adapt the FireWire 400 cable to newer computers… FireWire 800 to 400 adapter
Hope that list helps! Being fully prepared has saved me many times.