SCARM - Simple Computer Aided Railway Modeller
Prohunter - an android client for Product Hunt
RailModeller - RailModeller is a new application for creating model railroad and slot car layouts.
AnyRail - AnyRail makes model railroad design so easy, it's fun!
TRAX - Trax is a free web-based tool for planning your model railroad
WinTrack - Track planing software