Interesting take on “signing” your 3D models. It’s not visible once the part is finished, but is visible for a short while when the print is being produced. If you held the part up to the light, there’s a good chance you’d be able to see the signature - how do you guys feel about something like this?
http://hackaday.com/2013/01/07/signing-your-3d-prints/
this is very cool. I did a project where I embedded lots of layers of binary (as 1’s and 0’s) as infill a couple of years back on an early ToM. You could only read it while it was printing – 8 layers of binary, solid layers, 8 layers of binary. I shared the model around but no one ever had the patience to watch for this – just thought the sound was funny and i had made a pattern. 
(Though one person did read it and figured out that the squirrel was naming itself.)
Would be fun to have standard in-fill patterns based on this, or other arbitrary logos (OSHW gear anyone? :), as long as it didn’t have a negative engineering impact.
If you make them thin and don’t go too close to the perimeter, they’ll actually make the parts stronger by forcing more solid fill. They’ll also increase time and material needed for printing, which will annoy some people.
I wouldn’t mind it, but most times I download something I need to tweak it so I grab the source file(s) instead of STLs.
It’s like a nice Maker signature, for nerds that like to watch and listen to melodic infill - circle anyone!?
@Qitian_Dasheng_Sun_W This is true for me too, I think there is role for version tracking such tweeks in the real print as well as in the source/slic3r comments sections.
I would love to combine this idea with an inheritance model … every new fork adds a number or something like that … it would be like tree-rings