I found "Sita Sings The Blues" mentioned in Roger Ebert's blog, and it does indeed look as delightful as he says:
I put on the DVD and start watching. I am enchanted. I am swept away. I am smiling from one end of the film to the other. It is astonishingly original. It brings together four entirely separate elements and combines them into a great whimsical chord. You might think my attention would flag while watching An animated version of the epic Indian tale of Ramayana set to the 1920's jazz vocals of Annette Hanshaw. Quite the opposite. It quickens.