I just got this addicting Android game for my phone. It is called "Unblock Train." Thought some of you Android users might enjoy it. Not sure if its on the iphone app store too.
You pull the train from either end, get green train into station at lower left, red train not allowed in station. Here's a screen shot; you can get the idea:
There is another one called "Addictive Railroads" that I am going to try next.
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