Your credit card. If a filmmaker is still stuck, then I recommend throwing a brainstorming party with people who can help generate ideas. The guest list should match the amount of funds needed and the house being used. If it's a party where you want to get modest donations, then lower and middle income guests are invited to a lower or middle income home. If you want large donations, then wealthy people are invited to the posh home of another wealthy individual.
Homework is one of the major keys to all successful fundraising ventures.
First homework has to do with the project itself - making sure that the filmmaker knows everything there is to know about the film, its potential markets, its competition, etc. The bibliography on my website is the result of a dozen years of working in the field. It's a place to start doing some research and help a filmmaker address any blindspots. I've designed it to help empower a filmmaker to do this process effectively and intelligently. This is hard to do when you are in the middle of a project that seems to be the beginning, middle and end of your life.