A Stick Figure Guide to the Advanced Encryption Standard (2009)
moserware.com
moserware.com
[1] mostly me
Assuming you're specifically demanding stick figures doing math. It tends towards middle school level math and light comedy. The mystery of "point nine repeating" which was pretty interesting in 7th grade, and a skit along the lines of four technical professions try to split the check at a restaurant.
If someone knows of higher level stick figure math (aside from the linked AES discussion) that would be interesting.
Theoretically there are probably startup ideas around stick figure presentation online (a blogging / image service oriented strictly around sequential stick figures and comics?) or maybe in the infrastructure of something not as formalized and boring as visio but a little more cleaned up than a phone camera shot. Or an online service dedicated to cleaning up phone camera pics WRT hand drawings maybe even with OCR.
One of the features that helped it win the award is that it used file IO for "language bridging". Most of the other projects were pure VHDL. Our project used Python to verify the VHDL and Python AES implementations against each other. Fairly simple (OK, VHDL file IO isn't great) in practice but very powerful in effect.
We also had an interactive demo where you would enter a block and key. The Python implementation would encrypt the block and print the output. We would also run the key and block through ModelSim running our VHDL implementation (making sure to go through the PCIe bridge). The output was displayed to the user, allowing them to "see with their own eyes" that the implementation was correct. It was a powerful demonstration. The other team that also won implemented a Java simulator for their 3D "GPU", at least as much as a GPU you can do in 2 mm x 2 mm with ~35 um feature size standard gates.