Grid Physics Network (GriPhyN) project: www.griphyn.org
Chimera:  www.griphyn.org/chimera
GriPhyN Virtual Data Toolkit: http://www.cs.wisc.edu/vdt//index.html
Workflow Management Research Group: http://www.isi.edu/~deelman/wfm-rg/
International Virtual Data Grid Laboratory (iVDGL): http://www.ivdgl.org
Much of our work is done in collaboration with the AI group at ISI: http://www.isi.edu/ikcap/