I love clocks. My house is filled with different digital and mechanical clocks. I've always loved the Alien Clock, and I have an Atmos Clock I picked up on eBay a few years ago.
Now a nice designer clock has made it to the iPad and today only it is free to commemorate Earth Day. click.clock HD presents a striking display of time as the digits rotate around the screen. You can tap the screen and get iTunes controls. To skip from one track to another, drag your finger to the left or the right. Tapping and holding the screen will dim the clock, and if your are connected to external power the iPad auto-lock is disabled and you have a nice animated clock to display on your desk or a table. The clock works in either portrait or landscape mode.
Negatives? I'd like to see an alarm clock function. I was surprised the Apple clock app didn't make it over from the iPhone. I liked the world clock, and the alarms on the Apple app. Even the timers were handy.
Remember, click.clock HD is free today only in honor of Earth Day. Grab it if you 'have the time.'