I brought this up earlier so you can check out some of my discussion down here:
PS3 can't handle anything over 2TB so that is your limit. As you are a college student, I would suggest investing in some quality hard drives as you'd probably be bringing it around the campus and that sorta stuff.
Yes, just about any HDD will do. If you can't find one within your budget, buy a cheap internal HDD and a HD enclosure (it's basically a DIY option). You just put the HDD in your enclosure and voila!! you have an external hard drive!
Some enclosures are really savvy and have fans and all that sorta stuff and because you'll b using it to play games (i assume on ur ps3) you might want to invest in that as it will increase the life of your HDD.
The biggest companies are Western Digital and in close second Seagate but their product is down because of the recent floods in Thailand
. This will increase the price of hard drives by around 300% over the next 6 months (apparently).