I wrote a site to walk users through their first multisignature transaction.
http://multisig.bitwasp.co It lets you test you 2-of-2 transactions, and 2-of-3 transactions. The site puts forward a key to create the address, and you supply one or two more depending on the type of p2sh address.
A tutorial to walk users through the process of generating an address/public key, signing the transaction, and what the site will ask them to do:
http://thomas.bitwasp.co/?p=34I expect this sort of process (asking for a public key, asking users to sign a generated transaction) to be fairly common in the future, as multisig support is something people are calling out for but can't put into use yet really. Hopefully the code might help people looking to start accepting payments using multisignature addresses!
