Check out Jamesone's work at www.codeplex.com/psHyperV

Including:

Finding a VM
Get-VM, Choose-VM , Get-VMHost


Connecting to a VM
New-VMConnectSession


Discovering and manipulating Machine states
Get-VMState , Set-VMState , Convert-VmState,
Ping-VM , Shutdown-VM , Start-VM, Stop-VM, Suspend-VM
Get-VMKVP, Get-VMJPEG


Backing up, exporting and snapshotting VMs
Export-VM , Get-VMSnapshot, Choose-VMSnapshot , Apply-VMSnapshot , New-VMSnapshot ,Remove-VMSnapshot, Get-VMSnapshotTree, Get-VmBackupScript
Adding and removing VMs, configuring motherboard settings.
New-VM , Remove-VM , Set-VM , Get-VMCPUCount, Set-VMCPUCount, Get-VMMemory, Set-VMMemory


Manipulating Disk controllers, drives and disk images
Get-VMDiskController
Add-VMSCSIController , Remove-VMSCSIcontroller
Get-VMDriveByController , Add-VMDRIVE , Remove-VMdrive
Get-VMDiskByDrive, Add-VMDISK , Set-VMDisk, Get-VMDisk
Get-VMFloppyDisk , Add-VMFloppyDisk
Add-VMNewHardDisk


Manipluating Network Interface Cards
Get-VMNic , List-VMNic , Choose-VMNIC, Add-VMNIC, Remove-VMNIC , Set-VMNICAddress , Set-VMNICConnection , Get-VMNicport ,
Get-VMnicSwitch, Choose-VMSwitch, New-VMSwitchPort, Get-VMByMACaddress, Choose-VMExternalEthernet,
New-VMExternalSwitch, New-VMInternalSwitch,New-VmPrivateSwitch
Working with VHD files
Get-VHDDefaultPath, Get-VHDInfo, New-VHD, Compact-VHD, Test-VHD,Convert-VHD,Merge-VHD,Mount-VHD, Unmount-VHD

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