- RR Tycoon II Platinum
- RR Tycoon 3
- Sid Meier's Railroads!
Also available separately, but you save £2.48 if you get the pack!
Personally I'm more of a Transport Tycoon Deluxe person (even better now with the Open Source version), but I had a lot fun on the original RRT too!http://www.openttd.org/en/
(In case anyone wants Open Transport Tycoon Deluxe, it's free.)