From the home page of MPD:

Music Player Daemon (MPD) allows remote access for playing music (MP3, Ogg Vorbis, FLAC, AAC, Mod, and wave files) and managing playlists. MPD is designed for integrating a computer into a stereo system that provides control for music playback over a local network. It is also makes a great desktop [...]

Safe-Sleep is a technology from Apple — similar to the hibernation in Windows systems — that allows Mac OS X to save the contents of the entire RAM into the filesystem when the computer is put to sleep. This helps the system surviving a complete power loss, for example, like when replacing batteries on the [...]

This is a nice list of plug-ins for Greasemonkey that I’m using to make GMail more usable and productive. I hope one day GMail will integrate these.
Here’s the list:

Greasemonkey install
Next, you will have to restart Firefox so the Greasemonkey plug-in takes effect.

Conversation Preview
When this plug-in is enabled, right-clicking on any thread will display a bubble [...]