I cannot believe that this seemingly simple task is causing me so much agita. Mr. travelmad478 and I are trying to create a household shopping list that is shared between us and editable by either of us (him on iPhone, and me on Blackberry). Apparently, this is impossible unless we pay money to someone.

Google Docs: viewable by both of us, editable only on iPhone. My Blackberry can't edit it.

Dropbox: viewable by both of us, editable only on Blackberry. His iPhone can't edit it. (He can open and edit the document in Pages, but there's no way to save the edited document in Dropbox.)

Evernote: viewable by the person who created it, shareable only if you pay for Evernote Premium.

We have spent about an hour on this so far, with no success. I can't believe this is so difficult! I love the cloud but it is raining on me right now!

Remember the Milk?

You could put it as a calendar entry and use google calendar sync to share it between devices

You can sync/share multiple calendars, so you could if you wanted set up a google calendar specifically for sharing items without affecting your own real individual device calendars, and either of you can of course edit it online as well then too.

Obviously this wont be a word document, but its a way of getting what you seek

http://www.google.com/mobile/sync/
Plenty of tutorials on getting this to work if you google it