The best uses of QR codes are DEEP LINKS. Not as "mystery links", not to look modern, but to jump directly to one item in the middle of a hierarchy or a pool of options.
This is a great use of QR that is a mile away from the typical "scan this instead of typing two words and pressing .com" usage that is typical in the US and confuses people as to why QR even exists (as in this comic).
Check out how Tesco used QR codes in Korea to make a virtual grocery store: http://www.youtube.com/watch?v=nJVoYsBym88
This is a great use of QR that is a mile away from the typical "scan this instead of typing two words and pressing .com" usage that is typical in the US and confuses people as to why QR even exists (as in this comic).