With the 3DS finally being released outside of Japan, everyone will soon be getting their hands on one and making a Mii or two. A new feature of the 3DS is that you can get a QR code for your Mii to give to your friends, who can then scan the code with their 3DS and instantly get your Mii on their 3DS. In this thread you can post your QR codes for other people to scan into their 3DS, and you can also scan other people's Miis into your own 3DS!
I don't have any Miis yet other than my own personal one, but if you'd like to test out the QR Code feature (Or you really want my Mii on your 3DS), here he is: