As I stated, it is tough to find a desktop replacement laptop for 400 to 500 dollars. Until now, I didn't find anything cheeper than $670 that I am comfortable with recommending as a primary system. You'll always have slower cpu, lower resolution screens, integrated weak graphics cards, slower and lower ram... etc with these cheeper ones. The best two that I found until now are,
http://www.bestbuy.com/site/HP+-+Pa...ci_sku=9556296&ref=06&loc=01&id=1218123847586
this HP's price is 670 to 700. It is a good value for the money. Big screen 17", good battery life, hdmi, Blu Ray, 4gb ram expandable to 8gb (DDR2 which is slower than DDR3 and consumes more power, but ok)... Only issue is sound and that its weight is 7-8 lbs.
Verdict: Great value for the money. weight is justifiable as it is a 17" device and has blu ray. Sound card is not that good, but you can use a headset or a sound system. All in all, a good device
http://www.sonystyle.com/webapp/wcs...98552921644699998&N=4294953240#specifications
This one has a better cpu but doesn't have blu ray ($70 to add). It is 15.5" and weighs less than the former. Has 4 gb DDR3 which is better than the former. It starts at $700.
Verdict: Great for the value and looks great. I would go with this one if I were you.
Well, I don't like recommending just about anything especially if it is going to be your main device. If I find anything worthy for less than this, I will post right away. I doubt that I would find something, but we'll see.