I've seen that IIS has a problem with letting colons into URLs.  I also saw the suggestions others offered here. 
With the site I'm working on, I want to be able to pass titles of movies, books, etc., into my URL, colon included, like this:
mysite.com/Movie/Bob:The Return
This would be consumed by my MovieController, for example, as a string and used further down the line.
I realize that a colon is not ideal.  Does anyone have any other suggestions?  As poor as it currently is, I'm doing a find-and-replace from all colons (:) to another character, then a backwards replace when I want to consume it on the Controller end.