The plugins site is currently in development.
We've been looking to provide a higher-quality, spam-free experience at the plugins site for some time, and a major error on our part forced us to shut down the current site before we could put the new one in place. We are developing a new site, and you can follow along with its development on GitHub. For more information about this transition, including steps you can take as a plugin author to prepare, please read our post about what's going on.
Transparent Background Corners
This plugin allows you to add a variety of corners to objects without using images while still having the outside of the corner as transparent (as opposed to using the color of the objects behind it, like most other javascript corner techniques).
