Over the years I've written a great number of tools for my personal use. Here are some recent ones:

	SeisMac converts your recent Mac laptop into a seismograph. Version 2.0 adds many enhancements!
	ToneTester is a specialized ear-testing program
	SeisMaCalibrate calibrates your Mac's Sudden Motion Sensor
	SMSLib is an open source library for accessing the Sudden Motion Sensor. Includes smsutil, a command-line utility for capturing acceleration data.