Vexillology is the study of flags. I’ve posted before on this subject, and I again found something interesting. Someone sat down and made a ranking of all the flags of the world (including territories).
The #1 flag: Gambia
Dead last: Northern Mariana Islands (which they describe as being made with clip art)
Minnesota and Wisconsin have horrible flags. Both incorporate the state’s seal as the main element of the flag. As a result, it is impossible to draw. If a child can’t draw it, its a crappy flag.