SolarWinds new (and free!) VM Monitor is a desktop tool that continuously monitors a VMware® ESX Server and its virtual machines. With VM Monitor at your fingertips, you'll be able to track virtualization health at-a-glance and ensure your mission-critical apps never fail you.
SolarWinds free VM Monitor makes it easy to:

Quickly check the health of your VMware ESX Server by monitoring CPU and memory utilization 
Leverage best practice thresholds to monitor virtualized servers out-of-the-box 
View detailed virtual machine health statistics: VM name, IP address, & VM state, as well as processor, memory, & disk usage 
Prevent performance degradation in your virtualization environment