Whilst I’m sure 100s of other blogs have covered this before, something I feel invaluable are Wikipedia user scripts. These aren’t Greasemonkey scripts, but rather changes you make at the Wikipedia end. User scripts allow things ranging from previews of links, provide rich text editors to changing the links of ISBN numbers to your preferred site.

Once you have a Wikipedia account, you can install some pre-chosen user scripts by logging in and going to your ‘my preferences’ page and then clicking ‘Gadgets’ and selecting the ones you want.

An alternative way to install scripts, or scripts which aren’t supported by the automatic installer, is by typing in Special:MyPage/monobook.js in the search box and clicking ‘go’. On this page, go to edit and in a separate window/tab go to the list of scripts at Wikipedia:WikiProject User scripts/Scripts. On this page, choose the scripts you want and follow the installation instructions. To see the scripts, you might need to do a hard refresh by holding shift + refresh in Firefox or control + F5 in IE and/or purging the Wikipedia cache.

Some user scripts are specialised for Wikipedia power editors, but others like Navigation Popups are useful to pretty much everyone and once you’ve installed it, Wikipedia won’t seem right without them!

If you’re not using the Monobook skin, firstly you’re mad and secondly you’ll have to use the .js pages listed at this page as opposed to monobook.js.