I would be willing to offer my services as a speaker on any or all of the folowing topics:
The Financial Crisis Explained (entirely in semaphore, for the hearing-impaired)
String Theory: Are there really 11 dimensions, and can my creditors pursue me into the 6th and higher ones?
Epistemology: What can we know? That is, what can we be sure we know, or sure that we know we knew it, if indeed it is at all knowable. Or have we simply forgotten it and are too embarrassed to say anything?
Solving the Israeli-Palestinian conflict by means of cryptic crosswords.
I am open to other suggestions, as I can extemporize on almost any topic, as long as I am allowed to just make stuff up.