"...and just take the legal risks..." Wellll, what is there to gain by taking legal risks, as opposed to doing a research gig where we're trading in pennies for fictitious goods & services...? Please spell it out explicitly; there would have to be a very significant advantage to convince me to agree. Like maybe that the govt is about to pull all cash out of circulation and this is our last hope.... How about a crypto poker game, or crypto diplomacy (with fictitious money)? This would allow us to try some coin flip protocols, zero knowledge proofs etc. as well as crypto banking. Of course, cheating (trying to rig the coin tosses, spoof messages etc.) would be encouraged! That would allow us to find weak spots in the protocols, which are supposed to prevent this from happening. Then, at the next physical meeting, people could describe what kinds of things they did, and maybe the winner could get a small prize (e.g. be treated to dinner by the rest of the players).