Trainyard iPhone Game

I don't normally pimp out iPhone games, but a coworker pointed me to Trainyard and I grabbed it based purely on

• Looks fun and easy (perfect checkout line game)
  
• Lots of content in there
  
• Cheap ($0.99)
  
• Canadian based company
  

I'm not sure who else is involved, but when I find something that's nifty, I like to share.