A botnet startup. People sign up for the service, and install an open source program on their computer. The program can:

• Use their CPU cycles to perform arbitrary calculations.
• Use their network bandwidth to relay arbitrary data.
• Let the user add restrictions on when/how much it can do the above.

For every quantum of data transferred / calculated, the user earns a token. These tokens can then be used to buy bandwidth/cycles of other users on the network. You can also buy tokens for real money (including crypto-currency).

Any job that you choose to execute on the other users machines has to be somehow verified safe for those users (maybe the users have to be able to see the source before accepting, maybe the company has to authorize it, etc). The company also offers a package of common tasks you can use, such as DDoS, Tor/VPN relays, seedboxes, cryptocurrency mining and bruteforcing hashes/encryption/etc.