According to a cost estimate by iSuppli, Google's first Android phone, the T-Mobile G1, has an estimated bill-of-materials (BOM) of $143.89. For those of you keeping score, that puts it at $30.44 under the BOM cost of the iPhone.
The most costly part of the G1 comes from the baseband with its combination of ARM11 and ARM7 microprocessors, which account for $28.49 of the total cost. The G1's 3.2 inch touch screen comes in second for cost at $19.67, with the camera and radio frequency/power amplifier following as the third and fourth most expensive components.
iSuppli does state that the estimate is based purely on the cost of the components in the device, and not the software or manufacturing costs that go into it. Since the G1's major draw is the Android software, it would be interesting to see the rundown of software cost analysis at some point.