Answer:
Depends on where you live. Different places have different sales tax. As of now, a 120 GB PS3 Slim costs $299 without tax.
All PS3's have gone down in pricw lately due to the fact it has been out for a couple years. Recently, PS3 original and the slim versions have been reduced to $300.00. Others such as bundles cost alot more. see related link for latest USA PS3 prices
-------------------------------------------------------------------------------------------------------
In the UK you can get them for £235 (160gb).