In addition to the "Delta run" and New Berlin run desribed above, I have found the following to be profitable too.
VIPs from Manhatten to Freeport 2 in Bering. Bring back H-Fuel. Good for early traders, no Nomad or Corsair encounters.
VIPs from Manhatten to Planet Curaco in Cortez, stop on the way back and buy gold in Planet Los Angeles.
Diamonds from Scarborough Station in Newcastle to (can't remember the name of the station) the second base next to 1st planet on jump gate. Bring back optical chips. Very profitable, only 1 jump and no pirates. Gets a little boring.
BabyDoc
BabyDoc: Large Train
DragonKnight: Liberty Assault Frigate
Shadowen: Albatross Frigate
[MiD]The_Enforcer[Ace]: Rheinland bomber
[DJC]The_Kraken: Heugenot Cruiser