Nectome is a startup tasked with archiving the human brain and its memories: the hope is that one day, technology will advance to a point where people can be immortalized by having their thoughts and experiences uploaded to the cloud. Unfortunately, the process not only requires a $10,000 deposit, but euthanasia. Nectome’s storage service is not yet for sale and may not be for several years. Also still lacking is evidence that memories can be found in dead tissue. But the company has found a way to test the market. Following the example of electric-vehicle maker Tesla, it is sizing up demand by inviting prospective customers to join a waiting list for a deposit of $10,000, fully refundable if you change your mind.