Method:  Look around, the internet for starters.... 

Results:  Can you say the colours of the text out loud without speaking the words?  This is a really tough test.  “colour”

Conclusion:  In addition to showing movies, a DVD can work well as presenting tests,  puzzles, and illusions .  This psychological test for example is difficult for good readers.  It could be set up and may work well as a group activity.  With more searching I'm sure that I will be able to come up with many more.