I jumped onto codeplex.com for a random summary of the latest projects and stumbled across LINQ-TO-Javascript (JSLINQ). Pretty nifty idea.
Personally I'd like to see JSLINQ to be a jQuery overload -- that is, take the JSLINQ object definition and merge it with jQuery's object (at runtime) -- so that jQuery extensions can automagically work with JSLINQ objects. I suggested the idea here.