Template:Wikipedia
Use this template to link to an article at Wikipedia. There shouldn't be much overlap, but if there is, use this template.
Remember to use an underscore (_) instead of a space, as spaces break MediaWiki links (why couldn't they just pipe them??)
Um, basically, the use of the template is as follows: Adding {{Wikipedia}} creates a link to an article with the same name at Wikipedia with the link caption being the page's name. Adding {{Wikipedia|Article_Name}} produces a link to Article_Name with the link caption Article_Name (as MediaWiki hates spaces). Adding a second parameter, an article caption {{Wikipedia|Article_Name|Article name}} produces a link to Article_Name with a caption of Article name. The caption can be anything you want, for example {{Wikipedia|YTMND|The best site ever}} produces
Enjoy!
One last thing: because so many templates are right-aligned, you can add a 3rd parameter (the position, with a default value of right-aligned).