AC/DC's music video for "Rock n' Roll Train" is one that will bypass any workplace firewall--it's encoded in Excel format. Phil Clandillon and Steve Milbourne of Sony/BMG are the gurus behind this massive spreadsheet, which you can actually download here.
Unfortunately, Wired warns us that the Excel spreadsheet won't run on a Mac, and users will need to enable macros for optimal viewing. Or you can just check out the YouTube version of "Rock n' Roll Train" above in its full Excel glory.
Clandillon and Milbourne are fairly certain that this is the first time Excel has been exclusively used to create a music video.