As platter densities have increased, we have watched our drives grow. 20, 40, 80, 120, 250, and now 500GB drives are in the mainstream. Larger ones are starting to show up, but the 500 GB variety is gaining popularity. All the big players are in the market. It is these 500 GB monsters that I have with me today. From Western Digital I have their Caviar SE16 (WD5000KS), from Hitachi I have their Deskstar 7K500 (HDS725050KLA360), and from Seagate the Barracuda 7200.9 (ST3500641AS). Each are SATA II, 7200 RPM drives with 16MB of cache.