My neck and back are screwed up and need a light laptop! so I'm thinking of buying the Macbook Air.

Since I would only use it for FileMaker Pro development, I guess this laptop would be OK, right?

My question is: should I buy the 1.86GHz or the 2.13GHz? The first one has a 20GB SATA hard drive and the second one a 128GB solid-state drive. It appears that the SATA hard drive is faster writing but slower when reading when compared to the solid-state drive. Any tips on which one I should go for?

Thanks in advance!

That small screen would make development difficult.

IMHO the 15" screen is the minimum adequate for work (other than reading mail and web browsing).

I just bought a 15 inch and it's fine for working in the field, just. At home it's plugged into a 24 inch screen.

If only the 27 inch iMac was more portable...

The 15 inch is the minimum. What is the problem with your back? You need to transport the laptop a lot? If that is the case, maybe you could get a larger laptop and a laptop case with wheels.

Hard drive speed is not going to make much difference on local FileMaker development (although it's crucial in server deployment). The specs on any model/yr Air are fine, unless you're planning to do massive imports or something like that.

As for ergonomics, working on any laptop is about the worst setup you can have, unless you're going to plug in an external screen and/or keyboard.