5 ways to enhance your Wikipedia experience
1) Save a trip to Wikipedia.com with AQwikWiki or QuickWiki
Sometimes you run across a term on a webpage that you want to check out on Wikipedia, but you'd also like to finish reading the rest of the page. If you install these add-ons for Firefox, you can have both. AQwikWiki lets you highlight a term and right-click to insert the Wikipedia definition into the text in a yellow highlight. QuickWiki uses a customizable key combo plus a click on a word, and pops the definition up in a box. They're two different methods of doing basically the safe thing, but either way, you don't even have to bother leaving the page.
2) Access Wikipedia quickly from your iPhone with Wikiamo or Wikipanion
Both of these iPhone apps are designed to browse Wikipedia more efficiently from your iPhone. They each have their own unique feature sets, so you'll have to decide which one works better for you. This is much is for sure, though: they both make Wikipedia faster to search and easier to read than if you just browsed to it in Safari.
3) Download Wikipedia for offline browsing with Wikitaxi
If you're a Windows user, you can get WikiTaxi and keep a dump of Wikipedia on your hard drive, or even on a large thumbdrive. Apparently the entirety of the English version only takes up 8 gigs. Even when your Internet connection is down, or your school or work blocks Wikipedia for some reason, you can still have it with you.
4) Find what you're looking for with Wikiproxy and Smarter Wikipedia
Wikiproxy is a Greasemonkey script that links key terms on the webpages you browse to their corresponding Wikipedia pages. It's a bit like turning your web experience into one giant Wikipedia page.
Smarter Wikipedia recommends related pages within Wikipedia itself. With this script installed, you get a related pages menu on the Wikipedia sidebar that makes it even easier to kill an afternoon stumbling through fascinating new facts. Definitely essential for serious trivia junkies.
5) Edit Wikipedia more efficiently with WikEd
WikEd is a Greasemonkey script that opens up a full-featured WYSIWYG wiki editor that works on Wikipedia and some other wikis, too. If you can't remember how to do all those pesky wiki formatting codes when you edit Wikipedia articles, WikEd will help you out a lot. There's a whole palette of options that you can use by clicking, so you don't worry about getting the format wrong when you're making changes to an article.
And don't forget Simplepedia, a script that gives Wikipedia a stylish, minimalist facelift. It's been featured on Download Squad before, but it's definitely worth mentioning again.