I think that I will try to build a hackintosh and follow these directions

Rather than buy everything at once, I'm going to get piece by piece so that way I don't have to put that money up front.

Reason I want to do this? Because even though I love my iMac, I really miss a true desktop, and the Mac Pro is just too expensive!

For those of you who have built your own, does this one look good? I want a LOT of USB ports and at least 3 firewire ports.

I'm with you. I've been poking around sites and looking at building a PC for a while, and with the addition of our recent transfers it's piqued my interest.

This part does too, from the link;

At the moment, the cheapest Mac in the Apple store is a Mac mini sporting a 2.0GHz Core 2 Duo processor, 1GB of RAM, and a 120GB hard drive. For $300 more, I'm running a 3.0GHz Quad-Core processor, 8GB of RAM, a 1TB hard drive, and a damn saucy video card. I could have made this build much cheaper by skimping on hardware and still ended up with a great little machine, but I liked aiming for around the $800 price point from my last build—plus I really wanted to make it fly.

Antonio posted a couple of good resources in this thread too.

Well, you will probably build yours before me because I can't get all of the pieces at once. Be sure to start a thread on doing it so that we can talk about it!

I wonder if there are any limitations as far as what software works/doesn't work if any?

There shouldn't be any limitations unless it comes to games or programs that depend on a graphics card - Intel integrated graphics will be good for most other things, but not sufficent for a lot. It'd be a good idea to pick up a compatible and good graphics card. (I hope Apple announces they're going to use the latest and greatest from NVidea and ATI in January - I'd love to see how 3D in OS X flies with a Radeon 5870!)

Well, those instructions say to get this video card. I wonder how good it is?

EVGA 512-P3-N871-AR GeForce 9800 GTX+ 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Support Video Card

Click for full size

An ATi HD4870 should work fine too I would think.

I saw like 4 or 5 different brands of cards that are 4870. Are they all the same?

They should be the same - however, it wouldn't hurt to check and compare numbers in magazines like Maximum PC and CPU, or look for what others have to say in other PC/Mac building sites. Generally, though, you should (theoretically) be safe with anything for which Apple has created a driver for and that hasn't been heavily modified.

I would double the ram and make sure the video card can support Open CL.

You have to remember nVidia makes the GPU and other companies like EVGA make the card. Other words they can be very different from the core clock, video memory to the BIOS coding. You can have two of the exact same cards from two different vendors and each one will work slightly different, one might be fully compatible but the other can not support Quartz Extreme or no DVI support all because it uses a different hardware string.

Some people have been able to modify the KEXT files to use the proper string but you will only be able to go so far.