WordPress and Twitter Like Page?

Hi, Sorry if the question isn't that specific but I was just thinking if there was a way to make your homepage like the ones when you go to WordPress.com and Twitter.com where it shows Login / SignUp and a box on the side which shows a video and the bottom with links.

It's kinda hard to describe sorry if I'm making it complicated just go on the stie and check for yourself.

http://www.wordpress.com & http://www.twitter.com