via the Top500 blog
The guys at Top500.org are cracking open all that historical data they have and starting to spin some cool lists. Back in October they put together a list of the top 25 supercomputer sites of all time (where by “all time” they mean “since 1993”).
The ranking is determined using the sum of the Rmax share of every site in every list since 1993.
The methodology doesn’t really reflect longevity, though, just dominance (witness the Earth Simulator Center’s position at number 6, even though they’ve only been on the list since 2002).
DOE dominates the top of the list (NNSA and Office of Science), but there is good representation from the DOD (3 of their 6 centers make the list) and NASA. Only 7 of the sites are non-US; 4 of those are in Japan.