New Altcoin Promotes Fitness with 'Proof of Sweat'

Mining bitcoins chews up a lot of computing power for no other purpose than to sustain the network.

Now a team of Serbian developers has tried to crack the problem with a proof-of-concept altcoin that lets you mine coins simply by exercising.

While the coin is still in its very early days and problems remain to be ironed out, the concept may hold promise as a tool for institutions promoting fitness or as a way to lower health insurance premiums.

Some have been frankly bizarre: bumbacoin, for example, bafflingly enables people to 'mine' coins by trolling newsgroups with Jamaican expletives.

Primecoin solves prime numbers while mining coins, for example.

Peercoin, by the same developer, uses proof of stake, at least in part, which mines coins based on how many a person already owns, in an attempt to cut computing cycles and experiment with economics.

The trio's answer for that involves a daily mining limit of 10 mangocoinz per day, verified using a centralized, cloud-based service.

"If you mine three coins a day and click sync, you make three coins valid and to anyone you like, and you have seven coins left to mine in the day. Then it resets."

Attackers could generate multiple accounts, using phones on washing-machines or hacked clients, and continue to mine coins to the limit.

Theoretically, the software could use the GPS to check for a change in geographical position while the coins are being mined, to check that the miner is really walking or running.