Truth be told, it's quite old school, but it's tiny, very fast, easily made portable for use on a pendrive and can now handle tables.
See video tutorials on the homepage on tables.
Saves as .rtf, which avoids most malware, and can also export (but not import) as .epub.
Can be configured to make typewriter sounds, various spellcheck dictionaries available.
Home:
http://www.atlantiswordprocessor.com/en/
Download (2.5MB - yes, that's the program, not a downloader).
http://www.atlantiswordprocessor.com/en/downloads.htm
