StreetPass at HMV for 10% discount
Collect Mii characters for money off.
If you pop into your local HMV with your Nintendo 3DS and use its StreetPass feature to collect a "HMV store Mii", the nice people behind the tills will give you 10 per cent off a Nintendo 3DS game.
There's a long list of stores taking part in the promotion over at the HMV website.
With StreetPass activated, you can exchange Mii data and recent gameplay information with other Nintendo 3DS owners you pass, even when your system is in sleep mode.
You can then see collected Mii characters in the Mii Plaza.