For the 10th annual Regular Expression Day, I was trying to come up with an interactive game that was like "word search", except you are searching for "pattern matches". Under the hood, it was still doing a simple word search; but, the game board was constructed using words that I knew would adhere to established regular expression patterns.
The underlying technology is a Word Search Node.js module written by James Clark. Then, I took it and tried to wrap it in an Angular (v4) application. Things were going fairly well until I realized that there wasn't enough visual distinction between the selections; and, that overlapping selections weren't obvious enough to the user. In order to do that, I think I would have had to use SVG in order to outline the selections. Unfortunately, this is beyond my current skill set.
Still, was fun to try!