AIrport Extreme card in a G5 iMac, and inverter cable in an old iBook
iMac: I bought a new iMac and wanted to set up the old G5 iMac in the upstairs office for occasional use and needed to have it wireless capable to do so. I also still needed the old horse since I still use some apps that are Power PC which the new iMacs with Lion do NOT support. iBook: This was years ago, but the backlight on the screen went out. New screen - $300; inverter cable on ebay - $17; iFixit guide - priceless!
iMac: The card came fast and like new from iFixit. This is arguably the easiest thing you can do in the entire iFixit list. Anyone can do it! No photos required. iBook: I used iFixit years ago to replace an inverter backlight cable on my son's old ibook, and that required disassembling the entire computer and screen. It was quite a challenge, but with the iFixit guide, and the handy screw guide, we did it. The pics below are from that. Note the loop in the faulty inverter cable; I can't help but think it was installed that way.
iMac: Just realize it's 802.11g, so compared to having the iMac G5 hooked up via ethernet with very good isp speed, it might be a little slower (even with my airport extreme base station 802.11n dual band), but it's an easy, affordable solution for relocating an oldie but goodie computer! iBook: Patience and attention to detail.