I'm using a full body Invisible Shield underneath an iSkin for my 5G. After completely mangling my old iPod, I'm not taking any chances. I think Invisible Shields are the best screen protectors and iSkins are the best cases
I use an iSkin on my 3G and it has done a stella job. I accidently threw my ipod in the air when i was trying to open my car door and it bounced up to my waist after it hit the ground!
my dad got a load of fake ipod socks. I tried using them for a week or so and the scratches built up.