Cells for Rent: Inquire within...
I saw on CNET that Platform Computing released a module to its Platform Symphony Suite product which will enables Microsoft Excel to leverage grid computing. In other words, using their ADAPTER FOR MICROSOFT® EXCEL, you can string calculation-intensive worksheets together across 'commodity hardware' (as they called it). Aimed at the financial community, Platform anticipates that computations that would normally taken in upwards of hours could now be performed in minutes or even seconds.
Check it out and let me know if you want to borrow a few cycles...