As far as I can tell, Krrb is site that allows you to buy and sell from people all over the country. The have a small bookmarklet that you can use to copy from your posts on other sites and past into Krrb so you don’t have to re-write them. One of the sites was craigslist. Inevitably, craigslist’s lawyers sent them a Cease & Desist letter claiming copyright on every post on craigslist. An Open Letter to Craig Newmark explains what Krrb does and what craigslist is claiming and asks founder Craig Newmark to respond.
I’ve talked about this issue before and it’s pretty clear that craigslist really wants control over your postings and is willing to do whatever it takes to get it. It’s time a real competitor challenges them, but I don’t know of any.