Beowulf Project: CESDIS, NASA-Goddard Space Center,
  
  http://cesdis.gsfc.nasa.gov/beowulf/
Loki: Los Alamos National Laboratory,
  
  http://loki-www.lanl.gov/index.html
Hyglac and Naegling: Center for Advanced Computing Research,
  
  California Institute of Technology,
  
  http://www.cacr.caltech.edu/research/beowulf/
The Warren-Salmon Treecode:
  
  http://qso.lanl.gov/papers/Papers.html
Grendel: Department of Electrical and Computer Engineering, Clemson University,
  
  http://ece.clemson.edu/parl/grendel.htm
Hrothgar: Drexel University,
  
  http://einstein.drexel.edu/beowulf/Beowulf.html