Your search tool just appeared on our radar and while we appreciate your
desire to extend our search functionality it goes against the basic
intent of Craigslist to be a local tool. Also it's in direct violation
Additionally, you agree not to:
use automated means, including spiders, robots, crawlers, data mining
tools, or the like to download data from the Service - exception is
made for internet search engines (e.g. Google) and non-commercial
public archives (e.g. archive.org) that comply with our robots.txt
Please disable your tool for public use. If you refuse to do so we'll
be forced to block all the proxy servers that you're using.
You may have seen hacks for Google Maps all over the place, from finding local hotties to finding bloggers to, well, you name it. In fact, I remember the story about someone hacking Google Maps to create the game of Risk, which was also immediately yanked by Hasbro.
It seems to me that if people are thinking a step ahead of where you're at and are willing to create free tools that enhance your brand or site, the logical thing to do would be to talk to the developer and find out if they have other ideas for enhancements and just buy the ideas, no different than a consultant. At the very least I would purchase the tool/app from that person and incorporate it into my corporate site.