I'm not a linux guy, but if u want to fiddle around with it without duallboot stuff and messing up ur system, you can try the CD version. http://www.ubuntu.com/

Allready saw a normal installation running on an opensource meeting.. took ages ;-) Well c 4 urself..

Another funny site Scott Hanselman came up with is this mac-al-ike website, pretty need stuff. Apple with more then one mouse button ;-) No installation or whatsoever needed.
http://osx.portraitofakite.com/

The mono project also booting from CD. Get ur feed wet without the risk of bashing ur computer.
http://www.mono-live.com/
http://www.mono-project.com/Main_Page

4 tha python plp, take a look at this, Boo (is a .NET Language, feels a bit like Python)
http://www.hanselman.com/blog/BooShinyCLILanguage.aspx

So no more comments about me not posting non microsoft minded stuff!!!!!!!! ;-)