Another interesting variation of the blogroll/RSS aggregator. This time it comes from MyStack.com. Rather than my trying to explain how it works, this is a direct quote from the webpage. Might be useful as an automatic LinkBlog.
MyStack.com lets you create “Stacks”. A stack is a list of links, like a blogroll, and can be inserted into a weblog or webpage.
Unlike ordinary blogrolls, the list of links in a Stack changes. When you create a stack, you tell us what items you want us to stack for you. When the PubSub system finds new items that match your request, your Stack is immediately updated.