HanShi (2/28/2014)
I see your point although you can also colorcode the query-windows in SSMS. Register the instances in registered servers and apply a different color for each instance under the "connection properties" tab. If you connect through these registrations the query-windows will have a colored status bar.If you want to look at resource-usage of each separate SSMS I don't think that can easily be done. Perhaps the "process explorer" from Sysinternals can give you a bit more insight.
If you aren't familiar with Process Explorer, I would highly recommend it. For your specific need, they have a "Find" icon you can drag onto a specific window and it'll tell you all about it. There's a level of detail there that you won't find in many other tools.
Also, HanShi is exactly right about the Connection Properties tab...Use custom color check box. You can specify any color you want.