I think my favorite will always be the TGV. I had a chance to ride in the cab from Marseilles to Avignon as a guest of the French National railroad. I posted the video several months back. And you can find others on youtube.
When I was living in Birkenfeld, Germany, We use to go to paris pretty often, and would catch the ICE3/TGV in either K-town or Saarbrucken. I miss both trains.
Come to think of it, I miss Europe....