docX converter

Creating a new Office 2007 file format (.docx, .xltx) is a good way to push people to buying the new release. After all it is embarassing having to confess you work with old software and asking your partners to send stuff int the old format.
You can download a converter from Microsoft (if you have a valid legacy Office licence). It's been out for a while, but I notice many people don't know it.