Run8 by Run8 Studios is what you want. I just busted 4 coupler knuckles during a boring meeting because I didn't watch my slack coming off while accelerating up a +0.10 grade :)
www.run8studios.com
And if you want to peak train nerd like me: raildriver.com
www.run8studios.com
And if you want to peak train nerd like me: raildriver.com