Reddit mentions of Wireless PCIe Card BGN AR5BHB92 AR9280 Dual-band 2.4/5.0GHz 2x2 MIMO 300 Mbps 802.11b/g/n for DELL Toshiba Acer Sony Samsung Asus etc

Well, the internal adapter should be easily replacable. The wiki says it is this, for $25 shipped: http://amzn.com/B009HN63QQ

Besides that, I would install XP. Then you could use most wifi usb adapters.

Edit: Source: http://cr-48.wikispaces.com/Replacement+Parts

Also, ebay looks like $12 shipped.. even better.

You can get a much more powerful Hackintosh for the price of the mid-tier Mac mini.

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$105 - motherboard - GIGABYTE GA-H77N-WIFI
$220 - CPU -3.4GHz Intel Core i5-3570K
$129 - RAM - CORSAIR Vengeance LP 16GB (2 x 8GB) 240-Pin DDR3 SDRAM 1600MHz
$80 - case - BitFenix Prodigy Arctic White
$75 - power supply - SilverStone Strider Plus ST50F-P 500W
$80 - hard drive - Seagate Barracuda ST31000524AS 1TB 7200 RPM

$689 - total

\Concerning the wifi/bluetooth card included with this motherboard, the wifi doesn't work with Mac OS X, but the bluetooth functionality does. If you need both wifi and bluetooth, I would suggest replacing the built-in card with the AR5BHB92 300 Mbps 802.11b/g/n wifi card for $31. This card doesn't have bluetooth, so if you want bluetooth you will also need a USB bluetooth adapter. The $13 IOGEAR GBU521 Bluetooth 4.0 Micro Adapter USB is compatible with Mountain Lion.

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If you still have some extra money, you might consider a graphics card. The $260 GTX 760 is compatible with Lion/Mountain Lion. A discrete graphics card probably won't help much with video editing, but it's great for gaming.

Instructions for installing Mountain Lion on a Hackintosh can be found at TonyMacX86. http://www.tonymacx86.com/61-unibeast-install-os-x-mountain-lion-any-supported-intel-based-pc.html