[smacktoward]

The same reason a friendly drug dealer would offer a first hit free: to get you hooked.

Once you have a bunch of important documents locked up in Office file formats -- which Office is the only app guaranteed to be able to read reliably -- you have a great incentive down the road to start sending money to Microsoft so you can continue to access them.

[pionar]

I believe that's what they're doing, with the "free to view, pay to edit" model.

[niels_olson]

maybe it should be free to edit, pay to share?