Blockchain finance management
Idea: Allow shared ownership of funds between multiple people or subjects, where arbitrary rules can be governing the manipulation with these funds. Concept of "multisignature" is used here.
Functioning: After creating the contract with clear rules of funds management (owners are for example three people and each transaction needs to be signed by two of them) funds are sent to the contract address. Manipulating with these funds is now governed by the set of rules. These rules can be governing specific people having access to these funds, time conditions when they can manipulate with them or for example the maximal amount they can transfer.
Advantages: The responsibility of handling funds can be spread among multiple parties to increase the security of these funds (for example donations for a charity organisation). Thus stealing or manipulating with these funds without permission becomes much more difficult.
Disadvantages: Giving multisignature rights to malicious or irresponsible people can result in creation of "alliance" or the loss of private keys - therefore in the theft of funds or complete loss of access to them. Also, if a mistake is done in contract creation, the funds can be irreversibly locked in the contract.