Among other responsibilities, the Archives department preserves Microsoft history, be it old hardware, old software, old documentation, or ephemera. Last year, one of my colleagues was cleaning out his office because he was moving to Granada, and of the junk he was going to throw out, the Archives asked me to save the following:

• Windows NT Workstation 3.51 for PowerPC (box and CD)
• Windows NT Workstation 3.51 for Alpha AXP (CD only)
• Documentation for two internal UI libraries from over a decade ago
• Word 97/Excel 97 Service Pack 3 for Alpha AXP
• Microsoft Excel promotional pens
• Windows 95 launch event commemorative paperweight
• MSN 8 commemorative gold master CD and ship gift box
• MSN Internet Access promotional booklet and CD (unopened)
• An official CD of an internal build of a 1999 user interface project that was later abandoned (although its spirit survives in Windows XP).
• The official CD of pictures from the Windows XP RTM party (unopened)
• A lava lamp prize from an internal promotional campaign

and my favorite

• An HP RPN calculator which was issued to employees as part of the standard office equipment (back in the day).