re: NEAR Exhibits Unexplained Velocity Anomalies
Interstellar Helipause anomaly (one example, so far):
http://www.astrophys-space-sci-trans.net/2/33/2006/astra-2-33-2006.pdf">"the clarification of fundamental astrophysical processes like the acceleration of charged particles at a steller/(stellar, mho) wind termination shock" (as well as our understanding of our interstellar neighborhood.)
They're thinking about sending a Heliopause Explorer Mission. I'm hoping that New Horizons could be given a go for that before then since it's well on it's way. We'll see.