<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Wed, May 27, 2015 at 9:16 PM, Andrew <span dir="ltr"><<a href="mailto:onelineproof@gmail.com" target="_blank">onelineproof@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">You should also keep in mind the big picture when it comes to decentralization. If the hard drives (or tapes) can only be produced by a small number of large companies like Western Digital or Seagate, then you can't really count those for a decentralized system. A truly decentralized system would have the devices needed to participate in (and verify) the system be easily created by a regular user of the system without relying on a central power. So for example, the hard drives needed to store the bitcoin transaction records should be able to be produced at a regular person's home on a 3D printer starting from just the raw materials. I don't know how close we are to this ideal, but just pointing out that it needs to be considered. This is also a reason why I like that Bitcoin uses the simple SHA sum for mining instead of a more complicated function such as scrypt. It makes it easier for small scale entities to understand and to produce the ASIC miners.</blockquote></div><br>I am a huge fan of do-it-yourself at-home ASIC manufacturing. The original 4004 and earlier devices are within the scope of what could be accomplished in a home environment. The homecmos project is an interesting glimpse at these possibilities. Relevant-scale mining will most likely never be an option for home manufacturing, but bitcoin wallets and other devices can definitely be etched by hand or using maskless projector lithography.</div><div class="gmail_extra"><br></div><div class="gmail_extra">Here's what the homecmos group was up to:</div><div class="gmail_extra"><a href="https://code.google.com/p/homecmos/">https://code.google.com/p/homecmos/</a></div><div class="gmail_extra"><a href="http://homecmos.drawersteak.com/wiki/">http://homecmos.drawersteak.com/wiki/</a></div><div class="gmail_extra"><a href="http://diyhpl.us/~bryan/papers2/optics/photolithography/DIY%20fabrication%20of%20microstructures%20by%20projection%20photolithography.pdf">http://diyhpl.us/~bryan/papers2/optics/photolithography/DIY%20fabrication%20of%20microstructures%20by%20projection%20photolithography.pdf</a></div><div class="gmail_extra"><br></div><div class="gmail_extra">LCD projection lithography:</div><div class="gmail_extra"><a href="http://diyhpl.us/~bryan/papers2/optics/photolithography/Cell%20micropatterning%20using%20photopolymerization%20with%20a%20liquid%20crystal%20device%20(LCD)%20commercial%20projector%20-%20Itoga%20-%202003.pdf">http://diyhpl.us/~bryan/papers2/optics/photolithography/Cell%20micropatterning%20using%20photopolymerization%20with%20a%20liquid%20crystal%20device%20(LCD)%20commercial%20projector%20-%20Itoga%20-%202003.pdf</a></div><div class="gmail_extra"><a href="http://diyhpl.us/~bryan/papers2/optics/photolithography/Development%20of%20microfabrication%20technology%20with%20maskless%20photolithography%20device%20using%20LCD%20projector%20-%20Itoga%20-%202010.pdf">http://diyhpl.us/~bryan/papers2/optics/photolithography/Development%20of%20microfabrication%20technology%20with%20maskless%20photolithography%20device%20using%20LCD%20projector%20-%20Itoga%20-%202010.pdf</a></div><div class="gmail_extra"><a href="http://diyhpl.us/~bryan/papers2/optics/photolithography/Second-generation%20maskless%20photolithography%20device%20for%20surface%20micropatterning%20and%20microfluidic%20channel%20fabrication%20(using%20an%20LCD%20projector).pdf">http://diyhpl.us/~bryan/papers2/optics/photolithography/Second-generation%20maskless%20photolithography%20device%20for%20surface%20micropatterning%20and%20microfluidic%20channel%20fabrication%20(using%20an%20LCD%20projector).pdf</a><br></div><div class="gmail_extra"><br></div><div class="gmail_extra">DMD lithography:</div><div class="gmail_extra"><a href="http://diyhpl.us/~bryan/papers2/optics/photolithography/Maskless%20microscopic%20lithography%20through%20shaping%20ultraviolet%20(UV)%20laser%20with%20digital%20micromirror%20device%20(DMD)%20-%202013.pdf">http://diyhpl.us/~bryan/papers2/optics/photolithography/Maskless%20microscopic%20lithography%20through%20shaping%20ultraviolet%20(UV)%20laser%20with%20digital%20micromirror%20device%20(DMD)%20-%202013.pdf</a><br></div><div class="gmail_extra"><a href="http://diyhpl.us/~bryan/papers2/optics/photolithography/A%20maskless%20photolithographic%20prototyping%20system%20using%20a%20low-cost%20consumer%20projector%20and%20a%20microscope.pdf">http://diyhpl.us/~bryan/papers2/optics/photolithography/A%20maskless%20photolithographic%20prototyping%20system%20using%20a%20low-cost%20consumer%20projector%20and%20a%20microscope.pdf</a><br></div><div class="gmail_extra"><br></div><div class="gmail_extra">There's actually a method of doing this with conventional camera roll film:</div><div class="gmail_extra"><a href="https://groups.google.com/d/msg/diybio/5hpQXZ6hFKY/baGNfY_-Wx8J">https://groups.google.com/d/msg/diybio/5hpQXZ6hFKY/baGNfY_-Wx8J</a></div><div class="gmail_extra"><div><br></div><div class="gmail_signature">- Bryan<br><a href="http://heybryan.org/" target="_blank">http://heybryan.org/</a><br>1 512 203 0507</div>
</div></div>