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.
The Sony NV-U44 offers a few useful features that competing manufacturers have not yet implemented on their entry-level models.
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.
Pricing not available
Sony has positioned the otherwise good NV-U84 GPS device in an odd spot, where it's not as good a value as the models immediately above and below it in the NAV-U lineup.
The Sony NV-U83T is a seemingly attractive in-car GPS with a large display and useful navigation features, but it shows its ugly side with poor directions and subpar performance.