So, if your calculator has the command description app/add-on, you might enjoy diving into this weird bug. Choose a menu (Math, Matrix, Distr, etc.) and hover over a command of your choosing. Press '+', which opens up the command description. You will see a list of arguments and on the TI-84+C series the top of the screen will turn green. Then, press [2ND][STAT] to open up the LIST menu (you can also accomplish this bug by opening other menus from here, but not all of them work), but don't move your cursor.
Press [CLEAR] to exit the LIST menu and [GRAPH] to exit the command description. You will find all the commands you can see will be replaced by weird text including but not limited to brackets, question marks, numbers, and even your program names. You can scroll up the list (but not down; this will reset it) and even execute the commands, which will attempt to run programs with seemingly random names. Exiting the menu will reset the bug, returning everything to normal.
I haven't fully explored this bug on all on the menus nor on any versions other than the CSE, but I'm sure some experimentation will lead to interesting results (the DRAW menu is particularly odd). I'm not sure if this bug is of any real interest, but is strange enough to warrant some exploration.
The solution to a complex problem is often a simple answer.