This looks handy…
utilities
Sound Control
Handy app that restores functionality for digital sound output, including volume control via the keyboard. It also lets you set per-app volume controls.
Hangout Toolbox
Useful functionality to improve the Google Hangout experience
Browser Fairy
With Browser Fairy you can have individual default web browsers for every app and every web page.
How to use Chrome single-site browsers on a Mac
TNEF’s Enough
Handy OS X app to open winmail.dat attachments sent by Outlook users.