The most frustrating thing I’ve ever run into when working on networks with a large number of virtual machines is keeping track of which VM I am currently logged on to. Not to say it happens often, but If I had a nickel for every time I’ve been logged into a web server and been confused as to why I couldn’t find Active Directory Sites and Services then I’d be in pretty good shape.
There are a number of ways you can combat this, but one of my favorites is using the BgInfo tool. This utility, originally a SysInternals product, displays system information directly on the desktop of the machine its installed on. This can help us directly by displaying the computer name and IP address of the device we are using, and can also have the added benefit of displaying things such as OS information, memory, and free/used disk space.
The great thing about BgInfo is that it is not constantly polling your servers and having an impact in performance. It works based upon taking snapshots of the system information and creating a BMP file which overwrites your currently active desktop.
You can download BgInfo and read more about its setup and use here: http://technet.microsoft.com/en-us/sysinternals/bb897557.aspx