On 01/01/2016 10:21 AM, Josef Stautner wrote:
You can use an Amazon EC2 G-Instance and Scallion if you don't have a good GPU.
That is not a good idea, since then you are given them your private key. I trust Amazon, but not that much. People have posted on the /r/onions or /r/tor subreddit with similar pay-for-prefix services, and they continue to get shot down for this same reason. It's better to brute-force the prefix yourself.
Facebook's onion prefix is impressive, but I think it was a coincidence and good luck, which is also reiterated in this blog post: https://blog.torproject.org/blog/facebook-hidden-services-and-https-certs