A bootable backup drive. Because if the SSD fails in this thing it's not easily or cheaply replaced.
Well it is actually easy AND cheap to fix...
How do you figure cheap? Those drives cost a ton from third parties, and as much for an oem apple one used. I don't think apple will sell you one outright...
Also, pretty sure once an SSD bites the dust, there's no resurrecting it (anyone remember the old freezer trick for spinning HDs?). It's not a fixable thing really.
"cheap" and "easy" are relative.
......
Yes, the MBA's drive is anything but cheap and quick.
Beanoir...
For the vast majority of people it's not easy because they don't have the right tools or training to work on their Air. Nor should they really be working on their Air at all because the Air is a non-user-serviceable unit according to Apple.
Looking at OWC, their cheapest for the air is 120gb for $219.00. That isn't exactly pocket change for most people.
Just some simple points. ...and so not to sound like a jerk but I think you're wrong.