Within 2 weeks our new Programming Microsoft LINQ should be finally available! Today I just read a post about a LINQ to Regex implementation that we would have covered in our book if only we had a time machine.
When I thought at LINQ implementations in the past, I always underestimated that even if you use LINQ for a merely 1% of its capabilities, sometimes the Intellisense-enabling nature of LINQ is a good enough reason to switch your library-interface to a LINQ model. In reality, most of it is the magic of Intellisense + Extension Methods. Even if I don't use Regex very often, LINQ to Regex illustrated an illuminating concept to me.