New 100 Dollar Bill Unveiled Today

Today, Wednesday, April 21, 2010, the US Department of Treasury and Federal Reserve unveiled the design for a new $100 bill.
The design includes several anti-counterfeiting security measures and according to the Associated Press:

“disappearing Liberty Bell in an inkwell and a bright blue security ribbon composed of thousands of tiny lenses that magnify objects in mysterious ways.”

A 3D security ribbon on the front of the bill contains images of bells and 100s that move and change as the currency is tilted. The bell in the inkwell changes color from copper to green, which makes it seem to appear and disappear.
The new $100 bill will start circulating in February, 2011 and will replace the current ones which were designed in 1996.