Just installed Graffiti CMS, which is a great open source CMS. Graffiti is pretty slick it installs relatively easy and is ultra configurable.  Because it's open source, you can extend it, change it, pretty much change anything you want. It's latest version makes use of the .Net 3.5 framework, so adding and working with the latest technologies, such as Silverlight, should be a snap.

It also uses jQuery as it's core JavaScrip library, so adding animations, slideshows, etc. is a no brainer.

I'm still playing with the UI, but it won't be long before I start adding tons of custom features, skins, etc.  More to come on Graffiti soon!