This is a retired product, but fear not as there is a newer, better version available: COM-11823
Description: The BMP085 is a high-precision, ultra-low power digital barometer. It offers a measuring range of 300 to 1100 hPa with an absolute accuracy of down to 0.2 hPa. The BMP085 is based on piezo-resistive technology for EMC robustness, high accuracy and linearity as well as long term stability.
This sensor supports a voltage supply between 1.8 and 3.6VDC. It is designed to be connected directly to a micro-controller via the I²C bus
The BMP085 comes in an ultra-thin, 8-pin ceramic lead-less chip carrier (LCC) package.
A breakout board is available here!