Despite the sheer inability to keep a steady hand, setting up a Domino Rally was one of my favorite things to do growing up. I never managed to construct anything like the following videos, but it was always a fun experience — even though it almost always ended abruptly with an unexpected earthquake (also known as my younger cousins).
The first video is from the 2006 Domino Day Convention. The second video is from FlippyCat of YouTube. He stacks dominos on their side, purposely leaning them against each other. This style allows him to create nearly any object with relative ease.