Recently covered by Slashdot, Microsoft has re-released (ok, apparently the April releases were actually ‘preliminary versions‘…) the binary file format details for legacy (pre-Office 2007) Microsoft Office formats (direct link [64 MB file]) (licensing terms for using the information).
Notably absent: Microsoft Access.. the hardest file format to reverse engineer. In 2001-02 when I worked for an Anti-Virus startup company in Brookvale, NSW and part of my job was to extract Office macro code (VBA) from Office file formats. Access was the toughest, and I only managed to extract the macro code from Access 97 and 2000 – Never managed Access 2003 (native)….