This article mentions the availability of a PowerPack for VMware Lab Manager. The PowerPack has been created by Mark Kilfoil is available for download here. With this PowerPack, you can perform simple actions (like PowerOn, PowerOff, Suspend, Resume, Reset, SnapShot, Revert, ShutDown) on virtual machines.
On the topic of automated operations – VMLogix LabManager has broad based native automation support. Users can choose among a choice of rich automation operations that can be set and configured on role machines (including the ability to – pause the machine, execute a command on command line, install software, share folders, reboot machines, upload files, capture movies, execute user scripts, capture snapshots, revert, setting environment variables and several more!). Here is a snapshot of the available operations.