Having walked by this museum countless number of times, we finally spent an afternoon inside. We used a coupon from the Entertainment book, so we got in for a total of $6. Well worth it. i don't recommend going if you are just in a rush to do something quick because it is definitely worthwhile and even educational to take the time to read and watch the exhibits.
"Cotton Fields to Skyscrapers" did an excellent job summarizing the transition of the area. Living in an old cotton mill right now may have made it even more interesting for me.
There were a few videos or audio devices that were out of order, but for the most part everything was in good working order.
General note...don't mistake the trashcan by the door as a trashcan, it is for umbrellas.