I toyed with browser extensions briefly, but stopped because I couldn't figure out how to include jquery. After the workshop today I got inspired again, and wrote my first extension to add tooltips for airport codes.
Say you are reading some forum post with lots of airport codes:
My extension will add an airplane icon after each 3-letter airport code. Hover over the airplane gives you the name and location of the airport:
The code is on github: https://github.com/chiuki/airport-tooltip-extension. You can also download the packaged extension directly.
The parsing is pretty crude, and I didn't use any jquery at the end.
It only took me an hour or so to make the extension, and I'm quite happy with the results. Thank you Sharon for the excellent workshop!