What is the best external hard drive for me?

I know that this question has been asked countless times but I need some help figuring out the right solution for me. I've had my MBP for about a year and have decided to finally buy an external just in time for 4 years of school. I'm going to be using it strictly for backing up media on time machine and making copies on carbon copy cloner. I have about 50gb of 250gb used up on my internal HDD so far. I want to set it up so that it backs up overnight and then my MBP goes to sleep if such a thing is possible or while i'm doing work (it has to be quiet as it will be sitting on my desk). I've come to the conclusion that a desktop backup drive is most suitable for my needs.

My questions are:

What size should i get?
FireWire or USB?
Any suggestions off the apple site?

Thanks in advance

To do what you want, I'd get at least 1TB; I would prefer 2TB. Here is a great one:
OWC Mercury Elite-AL Pro FireWire 800/400, eSATA + USB2 external Solutions up to 2.0TB - Plug & Play Quad Interface

There are other fine ones; this is just what I use. You can assemble your own for a little less, and it's really easy. These are a little pricey, but worth it.

As far as backups, I use and recommend SuperDuper highly. It will make your backups when you want or on a schedule. The paid version allows smart-update. Very worthwhile feature. After you make the initial backup, smart-update just backs up the changes since your last backup. And support is fast, informative, and friendly. You can have SuperDuper do a host of things after backup; sleep the computer is one. SuperDuper also makes bootable clones unlike Time Machine.

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