Snap! Ayende Rahein has shown how Active Record can be used to implement a rules engine. I'd had some thoughts about backward-chaining and LINQ lately as part of a forthcoming post, it's nice to see some groundwork laid.
BTW, this is via Sam Gentile, whose \<a href="http://www.knowing.net/ct.ashx?id=4de0b8d1-1158-478b-8c47-6c48975adb9d&url=http%3a%2f%2fcodebetter.com%2fblogs%2fsam.gentile%2fdefault.aspx"" target=_blank rel="noopener noreferrer">blog is very high quality and who's looking to increase his subscriber base. Definitely subscribe if you're looking for high-end advice on agile techniques for advanced .NET development.