What an old-school blast!
I really don't think you can visit the 'Burgh without going on one of the inclines at least one time. I mean, seriously--these things are packed with history!
I'm afraid of heights, but once I got over the initial shock I was squirming around this thing looking for the best view to capture. Holy cow. Pittsburgh is already a gorgeous and fascinating city, but seeing it from the incline is incredible. You can almost picture it in the hustle and bustle of history.
I loved that it was cheap and informational. $4 to ride up and down was more than fair, plus you get to head out to the overlook and really soak in the view of the city. You can see the rivers coming together, the fountain at the point and the bridges all up and down the city.
Ahhhhhh... touristy, yes. Corny? Nope. Essential? Definitely.