I got an Asus laptop that while it might not be a "beast" it can model in Zbrush and Maya just fine and run games like Bad Company 2 pretty well. It cost me $600 on Craigslist. Like EQ said, save the money for a beast desktop so you can use that processing power to run a super high resolution monitor.
I have a Dell Precision M6500. I managed to get a refurbished one for £1500 - and saved about £900. Still comes with 3 year Business Warranty... i7 840QM, 8GB of RAM... although it can take up 24, 2 HDD slots and a further slot for a SSD drive. Oh, also a Firepro M7820 - however I am tempted to whip that out and try and…