As mentioned before, since getting an IPod for christmas I am a huge fan of podcasts. I find it's like listening to the radio but you decide what they talk about. Currently, my favourite feeds are Chaos Radio Express (in German) and the In Our Time BBC programme.
Recently, I was listening to an episode about Newton's Principia that discussed the scientific trends of the time when Newton published his seminal book. In Cambridge, I had learned before that Newton's remark that he was standing on the shoulders of giants was not meant as modest as it might sound. In fact, it's meaning was rather sarcastic as it was referring to Robert Hooke whose bad posture mad it obvious that Newton was in fact saying that he did not learn anything from him.
To me, that had always sounded rather reasonable given that the law that carries Hooke's name does not sound particularly deep from a modern perspective: It states that to leading order the elastic deformation is linear in applied force, basically a statement saying that no surprise happens and the first order does not vanish. Formulated this way quite a minor contribution compared to Newton's axioms and his inverse square law for gravity.
From the BBC programe, however, I learned that the situation is not that simple: In fact, Hooke had already found an inverse square law for gravity experimentally and suggested to Newton in a letter that that might me responsible for the elliptic motions of the planets. Hooke himself did (could?) not prove that and was asking Newton for his opinion.
Later in their life, the two men both of difficult character had an ongoing dispute about scientific priorities and this is where the famous quotation is from. The wikipedia page contains more information about it and buts it in the context of (wave) optics rather than gravity.