... and has no idea of what they really want. "I'll know it's the right one when I see it" and let's not forget the one when they tell you they have a lot of great contacts - then send you an invitation to linkedin. They'll tell you to feel free to show creative options then ask "is this normal?" - they want the cutting edge but pass out at the sight of blood.
When there's no written brief, no mention of schedule or available budget, it's going to run wild and you'll probably end up carry costs. This client is going to take up more of your time than they should and you're going to end up frustrated and wanting to kill the project.
Before initiating the design process, think, a problem well defined is half solved.
Here are a few helpful resources for questions to ask:
Writing A Successful Design Brief http://www.cleardesignuk.com/design-brief.html
How to Write the Perfect Brief http://www.harmony.co.uk/writing_brief.asp
How do you write a design brief? http://www.davidairey.com/how-do-you-write-a-graphic-design-brief/
How to Write a Web Site Creative Brief http://www.smileycat.com/miaow/archives/000226.php
How To Write An Effective Design Brief and Get The Design You Want! http://justcreativedesign.com/2008/09/26/how-to-write-an-effective-design-brief/
Writing a Brand Manifesto http://brand.blogs.com/mantra/2004/08/writing_a_brand.html