I know that what I am doing is not recommended, however, it has been working just fine for me. I have about 30 concurent projects that are spread over 11 external USB hard drives. It was a nighmare to try and track where all the files were, so I just put everything from one project on one drive (project files, raw footage, rendered files, etc). I am editing standard DV, not High Def. I have been doing this for over a year and have not had one problem with throughput, dropped frames, etc. I am not doing heavy compositing, but do sometimes have effects that take up 5-10 tracks at the same time. It sure has simplified my file tracking (although I still have a worksheet so I can find the project that I am looking for). I try and only keep 2-3 drives plugged in at one time because every time you plug a device into the USB hub it allocates space for that device and reduces the overall bandwidth for each one. In addition to the drives, I have a printer, mouse, scanner, graphics tablet and Ipod plugged into the USB. I am amazed at the flexability that USB provides. I am using standard internal 7200rpm drives that I put into external enclosures. Depending on what you are doing, you might find that this works for you also. Try a project on the drive you have now and see if it works.