WorldClock for DashClock is an extension for DashClock that let's you add a world clock to your lock screen. Easily see what time it is in another city in the world with a quick look at your lock screen.
You can customize the display including 24 hour format, icon display, custom name, with more customizations planned.
There is a pro version that allows you to add 3 clocks to your lock screen.
WorldClock for DashClock requires DashClock Widget by Roman Nurik: http://play.google.com/store/apps/details?id=net.nurik.roman.dashclock