You could do a lot worse than the Gateway NV55S05u for a solid RAM-hard drive combination and an all-around decent processor in a 15-inch laptop, provided you can live with poor battery life.
A large-screen laptop with very good performance, the Gateway NV7802u is an attractive choice for home or office.
It may not inspire, but for less than $600, the Gateway NV5807u is a great value as an all-around 15-inch laptop.
As shown: $599
Check manufacturer's site for availability