Openoffice might be free but it is a big download, especially if you are only wanting to read the contents of a single file. ODFReader is a useful alternative to this large download. It is a tiny (10KB) add-on for the Mozilla Firefox browser.

Once installed (Firefox needs a restart to complete) Openoffice documents can be opened in Firefox using the Open File option in the File menu.

This is a simple viewer so no editing is possible but it is a far quicker alternative to downloading the full version of Openoffice, especially for dial-up users.