Is there a way to get more than 3 international clocks in Windows Vista (or later)?
This How To Geek article describes how to add two extra international clocks but I'd like more.
Here are the steps:
Windows 7 supports only two additional time zones. If you want to set up more than two additional time zones, then you will have to install some 3rd party software like this one.
I found this freeware app from Microsoft, Microsoft Time Zone, but it requires .NET framework 1.1.
I've got .NET 4 installed but it doesn't seem to work with that, so I'm not sure this is viable on Windows 7, unless someone can suggest a fix.
I found this from this page, but most of the other apps listed look either sketchy, bloated or out of date.
While it's not a complete answer to your question you may find something of value hiding in the registry at:
Adding a 3rd entry doesn't seem to provide anything useful but it may well be a step in the right direction.
The World Clock - Orange desktop gadget, which I think is something to do with Orange France, is another option.
So overall this is about the best bet, but I am really surprised no-one has written anything better!
If you want more than one clock in your taskbar, you could try http://www.1stclock.com/