Open source rules engine with decent interface for writing rules

Question

I'm trying to locate an open source business rules engine that has a decent interface for building the rules.

OR at least one that works well on the .Net platform and has been updated sometime in the past 12 months.

Thanks,

Answer 1

NxBRE is one option.

http://sourceforge.net/projects/nxbre/#item3rd-5

Answer 2

.NET Application Block for Validation and Business Rules

Answer 3

You can use Reaction RuleML. The Rule Manager from Acumen Business has an adapter for business users to generate a valid RuleML document