Template:Bigthumb
The normal method of setting the size of a thumbnailed image [[Image:example.jpg|thumb|250px]] actually sets the maximum size of that image. If the source file is very small (such as an icon), it is not possible to "blow up" the image by setting the display size to 2x or 3x the actual size. Mediawiki's thumbnailing protocol only scales things down, not up. You can set a larger image size if you don't thumbnail the image, depriving you of the nifty 'frame' the thumbnail gives you.
This template is used to blowing up small images, but retain the standard image frame. (or at least a series of <div>s that look just like it.) The resulting thumbnail is right-floated. Left/center/none floating may be added in the future if users request it.
{{Bigthumb|example.jpg|250px|Optional Caption}}