I use office web apps for free, I don't know what you're doing wrong. Then again, you're probably confusing Office 365 with the Web Apps. Also, for 7 you could probably just ... are you able to download the SkyDrive app? I think that'd work, since it also makes a directory that auto-syncs with SkyDrive.
I can't tell you about the 365 site, though, that costs money. I just use Office 2013 RT edition and Web Apps on occasion when I want to access my files on my Mac since there isn't a better note app than OneNote for me.
Finally, let's hope it's a little sooner than 2027.