While not a complete replacement, it can be self-hosted or cheaply rented (I rented a basic set-up for free from a Swiss company). Got 2GB free storage. OFC this may limit you to using Libre Office, but I'm OK with that. My company uses Office365 web so I can use that if needed, but L.O. handles my Office Docs just fine! The bitching people do about MS Office compatibility usually revolve around some extreme Excel macro corner-cases, which don't affect most users. Or Powerpoint compatibility - I'll give you that one - there may be a few issues there.