Kai:
It sounds like you are trying to create something akin to the Links module in PostNuke or a Blogroll in popular blog systems, where it lists categorized links and indicates new/popular/recommended link/whatever. I am not aware of anything off the top of my head, but I was starting to build something like this for a couple of sites I am migrating from PostNuke. I’ll try and finish it soon and see if it’s what you are looking for, but basically, I think you just need a list of weblinks from a folder in MODx and a snippet to create the listing for you. So I bet our NewsListing snippet could be easily modified to handle this, because despite the name, it is simply a summarization tool for documents, which web links are a form of in MODx.
Also, you might want to check the bug tracker and see if someone has requested anything similar. If not, feel free to add a feature request for such a thing. I think it would be a very useful addition for many MODxians.