Just a couple months after I discovered what a great tool padmapper.com is for researching the rental market, Craigslist sends them a Cease and Desist letter. Too bad because this was obviously a huge listing source for Padmapper but outside of that, it was a great way for apartment seekers to interact with Craigslist. Padmapper's interactive search map made the process of locationg an apartment in a specific Chicago neighborhood so much easier. Does this mean Craigslist is going to start mapping their pads??