For fans of the one and only Arwel Wynn Jones, the creator of 221b.
He once posted a little photo of the smilie stencil helping to keep all sprayed smilies the same, and I developed the idea a bit further. 😉
Make your own things at Spreadshirt.net(EU) or Spreadshirt.com(USA)
Ready-made products at Redbubble (some examples below)