Here are a couple that come to mind:

TTS - Using flite - Works rather well except for the one volume bug where it blasts the speech at full volume.

TTSClock - using pcmplay

RioPlay Thread

SSH on the Empeg

emPacman

emphatic

SYLT Lyrics Plugin - For adding lyrics to mp3s for display in empathic

Squash thread

Skunk's Boot Logos - More boot logos then you will ever know what to do with.

Charcoalgray's Web Interface

Empeg Web Lite thread

Ill add some more if i can find them. This is a good idea Ive always wanted to start my own little list but never got around to it. *Just adding them as I find them no specific reason for the order.