I don't have any useable ideas I really /like/, but I have one I'm sure I can make work. I do have one idea down at the bottom that I'd love to use but it would need some new language features.
http://arrayboundserror.blogspot.com/2009/05/serialization-for-d-part-5-of-n.html As always: Comments, Please! (particularly on the "feature request")