I downloaded Roadsign Magic because we wanted signs for some fliers we were making at the school. The app itself is free, but not very useful for what I wanted without adding the $0.99 US Road signs and $0.99 background control and .jpg output.
I was generally pleased with the results. Here are some of my drafts as I learned to use the program.
It took 15 minutes to figure out I needed the $0.99 sign module, 10 minutes to figure out all the navigation (hint- really read the keystroke help before starting) and another 20 minutes to make all the signs. To edit text you click edit at the top first. That did not seem intuitive to me. This is also how you delete an element.
There is also an option to share these via Facebook and Twitter so I look forward to trolling with these next baseball season as well as creating nice looking signs for fliers.