Reference shelf

Atomic Collisions

Ion-solid interactions simulations
MARLOWE. (crystalline solids)
SRIM (TRIM), a popular Monte Carlo simulation code for random solids)
Molecular Dynamics programs: MDRANGE (U. Helsinki) and Moldy (U. Oxford). 
Molecular Dynamics resources.
Molecular Dynamics Software at UConn

Other Collision Software

Theoretical atomic collisions codes.
SigmaBasei, a data server on ion beam analysis, including analysis software
The Ion Beam Analysis Data Furnace

Physics (general)

General Physics software
Charged-particle optics software resources: and SIMION 3D-simulation program.

Mathematics

Molecular Visualization Resources
The Integrator solves integrals symbolically on-line
General and Math software
GAMS Mathematical software (NIST)
Graphical and numerical Extensions to Unix (Cornell)
Software for Atomic and Plasma Physics

Miscellaneous

The Internet Pilot to Physics (TIPTOP)
Yahoo Physics Guide
Physics Dictionary (Eric's Treasure Troves)
Excite Physics Resources Reviews
Physics Web (IUP)
PhysLink