Easy copyright -
Post a copy of your work by special delivery to yourself and DON'T open it. The work inside is legally copyrighted from the date shown on the envelope and there will be a record on the date the item was sent on the royal mail data files. In the event someone tries to steal your work after this date, your upopen (and there fore untampered with) piece which you can present to a judge is your proof! I have check this out myself. This is a legally reconised way of doing this.
PS you can also do this with film and audio too. You must also provide as much evidence as poss such as film scripts, unedited pieces, etc so it's all covered!
PSS It's only safe from the date on the package so if someone nicks it before you post, bad luck!