Bobby Diaz made a posting of some code samples of the Linq for NHibernate functions.
I haven't read through all of his linq posts yet, but this guy is doing some pretty ingenious stuff. I can't wait to start playing with Linq when I get some more time. I've been too busy with other development projects lately to really do any worthwhile research.
I would have imagined that Microsoft would have made it easier to make providers for Linq, but I guess thats not the case. I must admit that some of bobby's code is beyond my comprehension, but I think looking at it and trying to understand it only helps me realize more complex code. I feel its always good to be just inside that "wondering" area, it accelerates your thinking more and forces you to always be learning more.
Keep up the good work bobby!