VMWare is a software based solution that lets you run more than one Operating System on a single computer.
The specifics of how this magic is accomplished can be found under rarefied discussions of privileged mode execution, hardware virtualization hooks and ultra high speed context switching.
The results are spectacular. Tools like VMWare let you save money on power bills, hardware costs and service delivery across the enterprise, from the server room to the cubicle zone.
At least that's what you'll hear if you attend VMWorld 2009, opening today in San Francisco.
VMWorld.com is regrettably offline at press time, but according to custom the manufacturer can be expected to have all their champions coiffed and lined up to tout their virtual wares in a multiplicity of sessions.
Also according to custom, various interested parties are using the Twitter network to send short messages indicating their interests, thoughts and exultations.
The following is a tweeterbrowser diagram generated from such twitter messages, sent between 11:32 and 12:38 EST on Monday Aug 31, 2009.

The diagram shows the social network of 40 randomly selected twitter users who sent tweets containing the text #vmworld during the sample timeframe.
These 40 tweeple are seen to be part of a network of almost 4000 loosely connected individual accounts, with a reasonable dispersion of accounts that have large numbers of followers, and those that do not.
TweeterBrowser is a tool for studying participant behaviour on the Twitter social network. Enjoy VMWorld.