VMWare Server is a free virtualization product that installs on any existing server or powerful PC hardware and partitions a physical computer or server into multiple virtual machines by abstracting processor, memory, storage and networking resources, and thus able to further fully utilize the hardware and have the flexibility to run another same or operating system without the need of new computer.
Everybody can download VMWare Server for free from VMWare Server download page (current version is 1.0.2 build 39867). However, to install VMWare Server, users need to have serial number or product key, which is also available for free. From the download page, the Download button is so prominent that you might easily miss out the register link that is where you can get the free serial number(s), as the Download link will not provide any keys to install VMWare Server other than allows you to download the installer setup file.
So to get VMWare Server free serial number or product key, simply complete this registration. You can get for free up to 100 serial numbers at one go without any charges or fees.