WorldTime Clock

WorldTime Clock is a simple application that allows you to add multiple digital or analog clocks with different time zones.

You can completely customize all clocks including time zone, location, clock name, type (analog or digital), opacity, appearance (background color, font, time format, date, skin, flag), and synchronization options. You can also add reminders for important events including date and time, message, and sound (if you want), but you can´t schedule events like running a program, or opening a document, etc. The application sits on your system tray and you can control everything from there. You can add new clocks very easily and fast from there, and synchronize the clock with the server. The clocks can be moved across the screen as you want and you can also delete the clocks in snap when you don't need them anymore.
In short, WorldTime Clock is a simple application that is perfect for those who need multiple clocks, although the clocks are not very attractive. However, it is fully customizable and also offers reminders.