FontForge - Free (libre) font editor for Windows, Mac OS X and GNU+Linux
Numi App - Numi is a beautiful text calculator for Mac.
Glyphs - Make everything from dingbat webfonts to full-fledged text typefaces in the most Mac-like font...
SpeedCrunch - SpeedCrunch. SpeedCrunch is a high-precision scientific calculator featuring a fast, keyboard-driven user interface. It is free and open-source software, licensed under the GPL. Download Documentation Donate .
FontCreator - This professional font editor allows you to create and edit TrueType and OpenType fonts.
Qalculate! - Qalculate! is a multiplatform multi-purpose desktop calculator.