OpenOffice has largely been replaced by LibreOffice. It's a perfectly fine office suite, but the draw of Office 365 and Google Docs aren't the document editors themselves, it's that you get E-Mail, chat, file storage and PIM in the cloud with it.

The alternative isn't just LibreOffice, it's LibreOffice + Postfix + ejabberd + Samba + Apache + Radicale, which you all have to put on a server somewhere and set up individually.