GO transit is great, and I can't imagine where Toronto and surrounds would be without this vital and useful service. Here are some tips for the uninitiated. For starters, this is "honour system" rail. You purchase a ticket from any station. These are validated by sliding 'em into green boxes about four feet tall emblazoned with POP (Proof of Purchase). You then bring your punched ticket with you on the train and present it when asked by transit staff. You could try your luck, but I wouldn't bother: there is a $100 fine for not paying your fare.
The train is quick, clean, and the radius covered in an hour is quite impressive. There are usually local bus connections at each GO station, and coach buses take over routes at off-peak hours on certain lines.
Tickets can be purchased from a counter and machines that accept either debit or credit. There are only a few major routes so the GO system is pretty easy to navigate. My only major complaint: the trains don't run very late or as often as I would like. This might help win over a few more customers.
It's easy (and often fun) to complain about public services like GO Transit, but a lot of cities would kill (not literally) for a similar system connecting the metropolitan and suburban populations. It's pretty darn affordable and considering the millions of passengers that it transports each week, pretty reliable too.
Obligatory Title Pun: GO ahead, make my day.
Menu Readability: Their website is pretty good at providing route maps and fares.
Need to mention: Presto is a new system that allows you to load money on to a card which can then be 'tapped' to pay your fare. This is rolling out gradually to the various stations.
What this place teaches me about myself: As much as I loathe the morning train ride, I still support our ability to do so.