Up until recently, I'd been using SectionEx, but that component is not compatible with 2.5. I'm now on the hunt for a new, improved Category and Article listing component to use on my documentation site.
So far, this Component is a good start. It's nice and simple, and does the job, but it lacks features that would make it a knock-out winner. The ability to expand or collapse categories in the listing would be great, and would get that extra star from me. Otherwise, it does exactly what it says is does, and simple CSS can control the display of the listing.