Glimmer

The next generation plugin manager for WordPress.

Glimmer is an open-source WordPress extension that allows developers to create plugins that auto-install dependencies, warn bloggers about incompatabilities with their other plugins, and provides the flexibility of plugin updates from any web server.

Works with your existing plugins Simply add a your-plugin-name.glimmer file to your plugin to take advantage of all the cool Glimmer features. No configuration neccessary.
Makes distributing your plugin easy Distribute your plugin updates with Appcasts. New installs are also super easy - just distribute your .glimmer file and Glimmer will automatically install the lastest plugin version.
Compatability shouldn't be guesswork Before you have even activated your plugin Glimmer makes sure that your plugins will play nicely together. It even checks your WordPress & PHP versions for compatibility.
DRY. Set dependencies for third-party plugins Simplify your development process by extending third-party plugins. When you activate your plugin Glimmer will automatically install any dependencies that are missing.