If you want to have maximum capacity storage for your ps3/4 but dont want to go the 3.5" route with cables sticking out, you can get the spinpoint m9t 2.5" 9.5mm HDD for $150. The HGST travelstar 1.5TB cost about $120. So for only $30 more, you can get an extra 500GB. Well worth it, IMO.
Here are some pic.
Edit: Updated subject title. -Super_Nova2k13
This is old news. The external drive has been out for some time. Problem is, the drive inside has been plagued with issues when it is extracted from the enclosure. It is a 50/50 chance at best that the drive will work outside of the enclosure, and of course, you can't return the thing once you've cracked the housing, no matter how careful you are.
I cracked it open, and while it works fine with a PC, only 1tb was recognized by the PS3. The PS3 firmware cannot handle 2tb drives. it's not a problem with the drive itself, is my understanding.
The PS3 will only read 1TB and so far unless its changed the PS4 will read up to 1.5TB so putting in a larger drive then that has no advantage. Same as trying to put in 12MB of RAM in a PC when the operating system only registers 4MB