Remix Tools
Very useful tools to tweak outlines by Tim Ahrens.
More details on remix-tools.com.
Speedpunk
Outline curvature illustration tool for modern font editors by Jan Gerner.
More details on typophile.com.
UFO Quicklook
The UFO file format has become more and more popular in font production. With the QuickLook plugin, you can preview your fonts in finder by clicking the spacebar.
VFB Quicklook
This is the long-missing thumbnail and preview generator for FontLab Studio files. Now .vfb files are real citizens in MacOSX.