Free or FLOSS-ish virtual server?

[Starks]

Are there any decent free or open source alternatives to VMware Server?

[eldaria]

Hmmm, go back to the Virtualization Forum, then check the top for the Sticky Mega thread, the first page shows a list of Open and closed sourced Virtualization solutions. :-)

[Starks]

I read the thread, but I'm not sure of what I need.

Which products are more tuned to a server environment and which are more tuned to a workstation environment?