Though such a procedure is sure to void your warranty, you can (fairly) easily remove the iPhone 3G's screen, gaining access to internal components and allowing possible resolution of certain longstanding manufacturing issues as well as repair of hardware damage.
A post to the Hackintosh forums offers steps for doing so with a standard suction cup, such as the one used by some windsheild-mounted devices.
The poster, flash31, describes using the procedure to resolve the "light leak" issue that has affected some units:
- "Pull the suction cup toward you and the screen should come out (bottom first)
- You will see 3 cables running from the top right corner of the screen to the main board of the phone. 3 cables are numbered 1, 2, and 3. Remove the cables in that order. (Note: in the picture, my number 1 cable has already been detached, number 3 is underneath number 2)
- Once the three cables are detached, the entire LCD unit is now separate from the main board. I found two youtube videos that might aid.
- Look on the left side of your iPhone LCD unit; you will notice that Apple has already applied a small strip of electrical tape to the metal casing. Unfortunately, this strip is sometimes misaligned, causing light leakage. Simply add more electrical tape to anywhere you experience light leak. Note: the tape does NOT have to cover the black rubber gasket (the part that meets the bezel when assembled). Simply apply electrical tape to anywhere on the metal frame supporting the LCD unit. Apply tape to all the places you experience light leak.
- Reassemble the phone, reconnecting cables 1, 2, and 3, and then re-screw the two screws holding the LCD unit in place."
We certainly don't recommend performing this procedure in-house, though it does reveal the iPhone 3G's internals as significantly more accessible than those of its predecessor.