Eleven
Just jotting down a quick idea for the To-Make List: one of the few lecture that left me impressed was on how it is possible to use prolog to symbolically compute the derivative of an expression (a polynomial for example), basically by simply writing down the rules in form of horn clauses. It would be fun to make a literate program for the web out of it. Some JS glue code to feed a expression into Tau Prolog and maybe, to make it fancy, a mapping from the output to TeX and from there via Temml to MathML.
One day. When I am a bit less tired...