1) Is it possible to program a chain of transactions with multisig to form logic?
2) What is currently using multisig? Has there been any developments of anything running off the back of it other than a simple interface? (not to degenerate the website interfaces - those are fantastic to see)
If you want to play with the ideas at https://wiki.unsystem.net/index.php/Bitlaw I suggest the sx commandline tool as a starting point:
Blockchain transparency + multisig for organisations.
Accountability for actions taken within an organisation towards participants (shareholders, community .etc).
Tools for managing working groups.
Accounting tools.
Establish micropayment channels for ongoing payment of a good.
Trustless resilient purchasing by doing swaps, where swap_amount == tx_fee
Arbitration platform.
See arbcom on Wikipedia.
Enforcement?
Competitive/polycentric law?
Enabling different legal systems to interact.
Auditing and transparency.
Blockchain data for spends.
Multisig working groups.
Tools to issue securities/tokens
Traded p2p
Assurance contracts
SIGHASH_ANYONE_CAN_PAY -> multisig
Crowdfunding interface.
Bonds, securities, options, futures
Food trading within CIC + CSAs
Primary contract: A promises B to do X
Secondary contract (guaranteeing performance): C promises B that if A does not perform, then C will compensate B