You guys make me laugh. The iMac is not some cheap computer that was slapped together and then had a high price tag thrown on. It's a premium device made of premium materials. Does Apple put a mark up on the price? of course! but so do every other company, if they sold it for what it cost them that wouldn't be good business now would it? then there is the fact your getting the best customer service from any company on the planet, yeah Apple sure are ripping you off
EDIT: If another company can built an AiO that is to the same high standard, build quality, thinness and equally as powerful as an iMac and yet is considerably cheaper (and that company doesn't go bankrupt trying to sell it) THEN I'll believe an iMac is over priced.
The only thing "premium" on an iMac, and I have one, is the case, nothing else, the rest are off the shelf parts you can buy on Newegg, if you want to over pay for a fancy case, then by all means do it, but don't make patently false claims about the iMac, you will be called out on them