DCE Tools, extensis pxl smartscale, and "harry's filters" lol. It's a bunch of filters put together. All have their uses - and I use Neat Image as a Photoshop filter, not as a stand alone utility.
I have used several plug-ins from www.fredmiranda.com mainly I have found them to be good in reminding me the correct methods of doing things manually in PS, but if you don't have or want to take the time to learn these sure can speed up the workflow.