I'm thinking of getting a 250GB external hard drive to archive apps, music etc. Probably 5", can't seem to get 2.5" drives over 100GB but maybe I haven't looked hard enough. I was orignally going to archive my stuff onto dual-layer DVD-Rs. How do these formats compare in terms of long-term reliability. I know HDs fail after certain amount of use but if you don't use it every day it should last for quite a while, say 5 years? I have found that DVDs can scratch but thats because I keep them in spindles - not a great idea.