Hi, thank you for your question. I designed a protocol a while ago called Boost POW that allows people to buy proof of work. I think that is much better than locking. Locking is more like something for people who want to avoid pain but in order to use a costly signal you need to be willing to desire pain in order to achieve certain good things. The use case of a costly signal is to draw other peoples' attention to important information. We have a big problem with people getting more attention than they deserve. This is a problem with the world in general and it is a consequence of the way we communicate. Using a costly signal, people who are not famous can easily compete for attention with people who are already famous. This is the key to getting information out rapidly. Right now everything that spreads to many people must go through some famous person or well-connected organization. This is very good for talking about how to grow the economy without being diverted by nonsense ...