I've been looking into this recently... I think there are some recent Asus laptops which might fit the bill, although they might come in at a bit over your budget. They are the Asus UL series laptops, which feature switchable graphics (Intel GMA4500->Geforce G210M) and CULV dual cores. They look pretty sweet actually. The 14" one is
here and is cheaper than the 13" by about $100, so it is probably a better idea. I feel like if you get lucky you might be able to get something like this on sale for a lower price. Also, you might want to look into laptops with either Radeon 3200 or Geforce 9300/9400 IGP, as those should be pretty fast compared to an Intel IGP, and may be suitable for at least light gaming. I guess a netbook with Ion might be OK but the CPU will suck.
Oh, this Asus has a graphics card and is $700, but it's also 15", so that's two negatives. But perhaps you still want to look into it.
http://www.amazon.com/U50Vg-B1-15-6-Inc ... 74&sr=8-10