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I recommend the Griffin iClear. It's the best bang for your buck and looks great.

Another option would be the Invisible Shield. It's not a hard case, but it's scratch proof and covers the screen. If I were to do it over again, that's probably the route I'd go.
 
i also support the Griffin iClear, the hard case is very good and protects your iPod, i noticed that some of the stuff on the back (Apple logo, storage size, etc.) will rub onto the case but its still good
 
While we're on the topic, I'm after a plain slip case for my iPod touch. When I used my iPod, I want to use it 'naked', but when I put it in my bag, I want a plan, elegant, and protective case. Similar perhaps to what you used to get with the 3rd gen iPods or even the Apple leather ones. Any ideas? I've searched and searched, found nothing.
 
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