Have a lackluster datasheet for your sensor, but a demo app from the vendor that seems to calculate the value you need? If the app is written in .Net (Visual Basic or C#) -- and if it's Windows based, it probably is -- you might be able to decompile the app and find that magic formula you're looking for!
A collection of mini-tutorials on doing stuff with the Chumby Hacker Board. The CHB is a cool single board Linux computer that has much of the same hardware as the famous Chumby One. It's great for people who are experienced with Linux and want to have the power of a microcomputer with audio and video output while at the same time getting all the peripherals of a microcontroller such as analog-to-digital conversion, PWM outputs, sensors, bit twiddling, and broken-out GPIOs!
Ladyada and pt had an old NeXT keyboard with a strong desire to get it running on a modern computer. These keyboards are durable, super clicky, and very satisfying to use! We spent a few days and with a little research we got it working perfectly using an Arduino Micro as the go between. Now this lovely black deck works like any other USB keyboard. Sure it weighs more than our Macbook, but its worth it!
Your microcontroller probably has an ADC (analog -> digital converter) but does it have a DAC (digital -> analog converter)??? Now it can! This breakout board features the easy-to-use MCP4725 12-bit DAC. Control it via I2C and send it the value you want it to output, and the VOUT pin will have it. Great for audio / analog projects, such as when you can't use PWM but need a sine wave or adjustable bias point.