VGrADS uses Grid applications to motivate its research. In particular, we are deriving requirements for virtual grid (VG) functionality from the applications' needs. To date we have worked with half a dozen applications from several fields of science:

• Linked Environments for Atmospheric Discovery (LEAD) is currently the major application focus of VGrADS. VGrADS collaborates with the LEAD project, a large NSF Information Technology Research grant, in scheduling large meteorology computations on the Grid. Insights (from the VGrADS point of view) from this collaboration include the current "slot" management abstraction for timed allocation of resources and new scheduling and mapping mechanisms to take resource availability into account.
  
• Electron Micrograph ANalysis (EMAN) was an early example of a workflow application studied by VGrADS. Lessons learned from EMAN are now being applied to the LEAD application.
• Encyclopedia of Life (EOL) was an early application studied by VGrADS. It is no longer a focus of attention, since its requirements were well-supplied by other means.
• GridSAT was an application first studied by the GrADS project (a precursor to VGrADS). Lessons leaned from GridSAT were fundamental to VGrADS discussions of advanced techniques for fault tolerance and adaptation.
• Fault Tolerant Linear Algebra (FT-LA) is an application library for scientific computation. VGrADS uses it to refine methods for fault tolerance in VGs.
  
• Montage was an application from the National Virtual Observatory (NVO) that VGrADS and GrADS used as an example of a workflow application. Lessons from Montage have been applied to other workflow applications.