The one that seems most plausible is Google Docs. A lot of people I know use it, so far as I know their security is pretty good, and they seem to make it easy to send docs to people who aren't subscribers.
The thing I mostly do for my own use on Dropbox is save files into the Dropbox directory so that they can be edited on my PC, the laptop, or the iPad - the phone is less important (one reason why this isn't urgent) since all I do with it is occasionally send a photo to Dropbox. With Dropbox this works the same as saving any other file, it simply goes into the Dropbox directory on the device I'm using. Does this apply to Google Docs too?
Any good alternatives I should be looking at, that can be accessed regardless of operating system etc.?
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