Coming soon from mindsensors.com - a high precision infrared distance sensor. Available end of January.

Introducing series of high prevision infrared distance sensors using I2C bus digital interface. These sensors will provide reading directly in millimeters.

These sensors will have built-in calibrations to provide high resolution readings. When not in use, the sensor can be powerd down to conserve battery.

The sensors will come in ranges as follows -
Short range sensor: 4cm to 30cm
Medium range sensor: 10cm to 80cm
Long range sensor: 20cm to 150cm

Scheduled to be available by end of Jan 2007.