Please note, past this point, these tips are from 2005, and are probably way out of date.
Here are some tips for using Wikipedia, mostly based on my style of wikiing. If you see something here that you think can be done better or differently, don't hesitate to let me know.
Wikipedia scripts
Check out these scripts:
Navigation Popups - Hover over internal links to see what lies on the other side
Live Preview - Quick preview of your edits, without sending it to the server
Browser choice
Use a tabbed browser. I use Mozilla Firefox, but there are others. Tabs (especially with gestures or mouse-over tab-switching) will allow you to easily have several wikipages open at once, making it easier to check links as you write articles, and similar tasks that are easier with many pages open at once. If you do choose Firefox, I recommend also installing the "All-in-One Gestures", "Tabbrowser Preferences", and "undoclosetab" extensions, they give many excellent options to mold the browser.
In addition, I highly recommend using a browser that allows you to set up keywords/shortcuts to URLs that take variables, Firefox lets you do this as well.
Quick wiki bookmark shortcuts
Set up a keyword/shortcut to topics in wikipedia, this is one way of reducing your server load on wikipedia, and saving yourself some time by leaving old tabs that you need open.
In the address bar, type 'check "some text in Wikipedia I think is a copyvio"', it searches google for '-wikipedia -dictionary -encyclopedia "some stuff I think is a copyvio."'
See your results, not containing any wikipedia or wikipedia mirror results!
The %s in the URL is browser dependant, so if you use something else, check on it.
Firefox Wikipedia extension
There is also a Wikipedia extension for Mozilla Firefox, located here. It provides a toolbar and context menu for editing Wikipedia. I actually don't use it, but you might find it useful.