At first an admission, I have yet to see the movie "The Crazies" so I can not say with any authority whether or not it belongs on a list of top things about Iowa. I am going out on a limb on this one but think that the limb is likely sturdy for a few reasons:
How many feature films have been filmed in Iowa, most will likely make the list.
How bad can a film be that features Gary Jules' version of Mad World?
The trailer is pretty creepy and features some nice shots of small town Iowa.
Radha Mitchell may not be Iowan (she is Australian, so much for few Aussies in Iowa), but she is very attractive.