Wikipedia Popups
My Wikipedia investigations of late (I want to propose a major new feature and I’m feeling out the “deep” WIkipedia) uncovered the little known fact that as a registered user you can have a personal stylesheet and javascript file — which means that with a little know-how you can have Wikipedia looking and feeling exactly how you want it — and have this look-and-feel follow you around with your account. If you use the default skin, Monobook WP, your personal stylesheet and js file are monobook.css and monobook.js. There’s help here.
This opens the door to all sorts of customizing galore — skins, plugins, new features… — and while I still have to dig into it properly, so far I’ve found the amazing Navigation popups script, which pops up a small, smart (meaning it does interesting stuff depending on context) preview of any Wikipedia link you hover onto. Its slightly annoying until you get used to it, but once you do get it into your “work”-flow it’s very sweet — blazingly fast and with tons of handy extra options. Installing it is a snap too, just add one line to your monobook.js.