Craigslist and Google Reader

I've been using it and it works wonders. The basic idea is:

1. go on Craigslist and do a search
   
1. such as PS3 Game less than $40 http://newyork.craigslist.org/search/sss?query=PS3+game&minAsk=min&maxAsk=40
2. get the RSS feed version ( bottom right corner )
1. http://newyork.craigslist.org/search/sss?query=PS3+game&minAsk=min&maxAsk=40&format=rss
3. Subscribe to the RSS feed via Google Reader

This automatically will keep track of what items you have read and allow you to tag your content.

Here is a more detailed tutorial from SeattleBubble.com : How To: Use Craigslist & RSS to Find a Great Rental