I am looking for a wiki with the following features:
Online & free
For small teams (from 5 to 15-20 people)
Internal usage only (so not public access unless you have an account)
Able to edit documents like Microsoft Word (WYSIWYG)
Manage spreadsheets
Able to export the content in reusable formats like Markdown, DOC, text etc. to avoid locked-in situations
Is there anything like that?