Career prospects in theoretical physics after nightmare PhD
I think you should consider transferring to another grad school. Certainly prospects on the post-doc market won't be good without any publications, interesting work, or a strong letter of recommendation. On the other hand, your advisor's grant expiring and no one else being able to take you gives you a very good reason to want to change grad schools.

Your former advisor's letter will be crucial. If he confirms your story about the grant falling through and no one else being able to take you, you should be able to transfer no problem. If he hints that your conduct contributed to your situation, you could be in a pickle. Good luck!