geekery:

online math-and-biology stuff.. They have a discussion of the Rosenzweig-MacArthur predator-prey model that I need to take a look at...the diagrams look like artwork.

(and seriously, you don't really have to be either a biologist or a mathematician for it - there's a lot of interesting stuff on the history of the understanding of concepts, and periodic cycles, and it's all written in "intelligent lay-person" terms). Good site - I'll have to check out all of its features.