I had IMG image of our server which I wanted to mount on our virtual machine. Since I was using VMWare Player which supports VMDK so I was finding a way to mount IMG on virtual machine or convert it to VMDK. I found StartWind V2V Converter which made this easy. You can download it from here.
The whole process took only around 20-25 min where it converted about 10G of IMG file into VMDK. Cool!
I was then able to just create a new VM and add this VMDK there. Since it was bootable I was easily able to boot the VM and login.
You can use this tool to convert VMDK, VHD, and IMG to each other as well. A nice utility and on top of it, it is free.