Is there a way that I can put an external USB hard drive "through its paces" to test if it is failing? Im after some sort of tool that reads/writes a bunch of data and sees if the drive is doing what it should (I actually have no idea what it should do to thoroughly test the drive...). I tried using gsmartcontrol from terminal but apparently my external USB drives don't support SMART. Any ideas on what I can use (preferably free) to test my drives? I have a few that Im a bit unsure about and don't know whether to trust or not... Thanks.