I found 31 train sims

How Many Train Sims Can You Name? I've listed 31 unique ones below (one is listed under two categories). I think there are more.

Dispatching/Signaling
NXSYS. (http://nxsys.nycsubway.org/)
SIAM. (http://www.siam.co.uk/index.html)
Signalling Centre Software. (http://www.sigcent.com/)
Train Dispatcher. (http://www.signalcc.com/)

Railway Modeling
Rail3D. (http://www.rail3d.net/)
JBSS Bahn. (http://www.jbss.de/hpg_eng.htm)
Zusi - Der Zugsimulator. (http://www.zusi.de/)

Cab-View Drive-It
BVE. (http://mackoy.cool.ne.jp/)
Loksim3D. (http://www.loksim3d.de/LokSim3D/loksim3d.html)
Mechanik. (http://www.thelocomotivecab.com/mechanik.html)
Real Railway. (http://www.realrailway.com/)
Simulatore di treno 3.00. (http://signa.texnet.it/sbapao/)
Train Cab Simyulator. (http://www.digiflyer.nl/eriki/trains/index.htm)
Train Simulator. (http://www.ongakukan.co.jp/)
TrainMaster. (http://www.trainmaster.com/)
YKTrain. (http://www.geocities.jp/yuuchankellyy/indexe.html)

Full-Featured 3D
Eisenbahn Professional. (http://www.softwareuntergrund.net)
Micrososft Train Simulator. (http://www.microsoft.com/games/trainsimulator)
Rail Simulator. (http://www.railsimulator.com/)
SpoorSim. (http://www.modellbahnsoftware.de/Simu/spoorsim.htm)
Trainz. (http://www.auran.com/)

Video
A Train 6. (http://atrain6.midasinteractive.com/)
Densya de Go! (Let's Go By Train!). (http://members.aol.com/netransi10/densya/densya.html)
Train Simulator. (http://www.ongakukan.co.jp/)

Strategy
A Train 6. (http://atrain6.midasinteractive.com/)
Locomotion. (http://www.atari.com/us/games/locomotion/pc)
RR Tycoon. (http://www.poptop.com/)
Transport Giant. (http://www.transportgiant.com/)

Professional
SYSTRA's RAILSIM v7. (http://www.railsim.com/)

Other
Train Games (http://www.traingames.freeservers.com/HOMEPAGE.HTM)
Black Five (devleopment suspended - http://www.black5.co.uk/)
Amiga Train Driver