Are you a heavy user of the online classified website Craigslist? If so, then you definitely have to look at CraigsPal, a desktop software program designed just for searching Craigslist. The application is available in two different versions, one free and one paid. The free version lets you search across cities, states, and countries, filter content, use negative searches (-keyword), preview listings/photos, sort by price or date, flag spam, and has several keyboard shortcuts.
The paid version, however, is for the true Craigslist fanatic. With CraigsPal Pro ($29.99), you can receive mobile SMS and email alerts, save favorite searches, backup your user data, automate searches, and you have access to free updates for the life of the program.
Of course, if you just want to search all the Craigslist sites, you don’t need an app to do so: Search All Craig's lets you do that from one simple web page. And if you really want to delve into all that is Craigslist, Lifehacker has the definitive Craigslist Power Users Guide.