I need an external hard drive to make backups and move stuff between my computers, but with so many choices i don't know what to get. First off, which brands are considered descent? I was thinking may be Western Digital or Seagate since they make good regular HD, i'm getting those 2 for my first build. Second question has to deal with the type of HD i should get, i'm thinking of USB 2.0. But there are others available such as USB 2.0/IEEE 1394a or b, USB 2.0/IEEE 1394a/SATA or eSATA and many others. i'm not even sure why they have so many different kinds. I'd appreciate any suggestions.