OMG Cω is Awesome! You should check it out
I wrote a short article here showing some of the very interesting language features I found in Comega, a language created by Microsoft Research. If code like this (especially lines 18-22 and 26-27)
producing output like that shown below sounds interesting to you then you should have a look.
Update: Jayson has a nice overview of Cw (back when it was called Xen) here.