I’m always looking for more snippets of code, markup, etc. to add to my always growing TextExpander list of bits I’ll reuse. This is a definite one I immediately added.
Regardless, this is a quick and simple way to highlight on rollover (and touch with the JS addition) tabular data.
It’s a short (less than five minutes) video/presentation back from CodeMash 2012. It’s hilarious and sadly insightful.