Juan Caballero, Theocharis Kampouris, Dawn Song, and Jia Wang published some interesting extensions at this year's NDSS of the work presented by Harish Sethu and me at CCS '04.
Both papers examine the software diversity problem, which states that networks of systems would be more secure if they minimized the number of possible common mode faults by running different software and operating systems, by relating it to the graph coloring problem. The thesis of both papers is that software diversity can be improved by using graph coloring algorithms to maximize diverse software allocation.
This title of this post's implication is only in jest, as I am incredibly happy to see our idea extended by the research community.