Prior to July 2005, only three comet nuclei had been observed directly – Halley, Borrelly and Wild 2. On July 4th, 2005 the Deep Impact mission crashed into comet Tempel 1 (on purpose) with its impactor spacecraft and observed the show from the flyby spacecraft. The flyby spacecraft survived the encounter in good working order, and NASA funded a follow-on mission to encounter one more comet, Hartley 2 on November 4th, 2010. Despite both basically looking like potatoes, there are some significant differences in the two nuclei that are important to understanding comets in general. I’ll give some background on why we should care about comets, some history of the Deep Impact mission, and show lots of cool images of comets while describing what new insights we have gained using our workhorse spacecraft.