VMware ESX 3i for free
From virtualization.info:
VMware finally made the move that everybody predicted and was awaited for a long time: releasing its hypervisor for free.
During the Q2 2008 earnings call the company announced that before the end of July (the planned date is July 28) it will release the Update 2 for VMware Infrastructure 3.5 and that will give away the lightweight edition of the product, ESX 3i, for free.
Totally, awesome.