Chrome: Sometimes, when you're reading Wikipedia, you need to open up another article to better understand the one you're reading. Wikipreview saves you from opening them in tabs by showing you a preview of that article when you mouse over it.
We've all been there: you open up Wikipedia to learn about one thing, and end up following a trail of links just to try and understand the first thing you opened. You don't necessarily need to read the entirety of every article it links to, you just need a general idea of what a specific term means so you can better understand what you're reading. Wikipreview solves this problem by previewing articles when you mouse over their link in Wikipedia. It won't save you from going off on a tangent just because you're curious, but it will help you minimise the tab-opening you need to get through a specific article.
WikiPreview is a free download, works wherever Google Chrome does.