This might not be the solution you are looking for but I've attached a small, portable 3TB drive to my laptop. I work on pictures a lot while at my kids soccer practice, dance class, etc. so I wanted the ability to have a lot of my pics with me to work on backlog editing. I have 2 USB ports so I keep the hard drive pretty much permanently plugged into one of them. I bought a short USB cord with a right angle connector and I've attached the hard drive to the lid of my computer with 3M picture hanging strips. I've wrangled the cord through two 3M cord clips and attached that to the lid as well. I haven't had any problems with this scenario. If I'm pulling it in and out of my backpack a lot I do make sure to push on it a bit to make sure I haven't giggled it loose. I will warn you though that sometimes at coffee shops or whatever people look at me and the computer strange because it is an odd setup.

If you are interested it's a Western Digital My Passport Ultra 3 TB Portable External Hard Drive.

You didn't specifically ask about backups but ... for backups I use Crash Plan for offsite storage (which I love) and Time Machine for quick local backups (in case of catastrophic disk failure). I'm a belt and suspenders kind of girl when it comes to backups. ;) Crash Plan is AWESOME!!! When I'm connected to the Internet it backs up anything that has changed every 15 minutes. Restores are quick as well ... unless you need to restore your whole hard drive --- which is why I do Time Machine for that purpose. Crash Plan can send you a disk with your backup on it to restore a whole disk from but I think that would be too long of a wait for me.

Anyway, i hope that helps.