Slide in div

Can someone tell me how the site nasty girl . com created the code for their slide in newsletter signup form? I just need the slide in effect with the close button for a message. Form info is not needed.

Thank you

One way of doing it is to use css positioning to first place the sliding div outside of its container and then use setInterval() and/or setTimeout() to gradually change the top, left, bottom, right styles (depending on the direction of the sliding) to create the sliding animation.