I like "black sticks" - the hard nylon probes available from Apple and others:
http://mac.macrecycling.com/apple-nylon-probespudger-tool-black-stick-new-p-100693.html
They are softer than metal spudgers, yet firmer than the tools usually offered as "iPod opening tools". They will at least last thru the repair of a product, while the softer tools have failed on me before even getting a repair started. If you can get a source for these and offer them at iFixIt, it will be a win for anyone working on product repairs featured here!
The source listed above has been confirmed to offer the exact same part used by Apple, I am not sure if they are the same item offered by iFixIt: http://www.ifixit.com/Apple-Parts/Heavy-duty-Spudger/IF145-013