KoalaCalc is a free multi-purpose calculator for Mac OS X. In its compacted state, it looks similar to the standard calculator that comes with Mac OS X. However, simply click the 'advanced' button and KoalaCalc comes to life to become one of the most advanced scientific, conversion, statistical and expression calculators available.
What is new in this release:
Fixed bug which caused speech problems under Mac OS X 10.7 (Lion)