One of the things I'm working on lately involves interaction between a TiddlyWiki instance and a running BASIC program embedded in TiddlyWiki.
Although I don't have that kind of interaction built into this BASIC program, I'm thinking that could be cool to dynamically adjust the parameters of the program (via TiddlyWiki) as the program is running.
A ton of BASIC code out there that could be enhanced with TiddlyWiki goodness ...