Doesn't OS X go for $129 from Apple? That's a bit of markup. It's not much more money to go from their machine to a Mini that you know will work right out of the box, has a full warranty, has all the software, and has Apple's support department behind it. Isn't that extra worth $45?
You can get if for $109 from Amazon. Psystar marks the retail up to $155 when they sell their clones.