There was a time when comparisons were made between Obama's signature and the circular Bismillah (statement of faith in Islam). Those have all been scrubbed from a Google search. Even the circular Bismillah images have been scrubbed to the point that I only found one that even closely resembles his signature now.
However, as a student of Islam (yes, I am), I know exactly what I, and the rest of the world, see in his signature.