Is there a way for Spotlight or Launchbar or Quicksilver or similar to just return matching folders not files?
The fastest way using spotlight is to add kind:folder to the search term in the spotlight field.



You can use booleans, metadata tags like kind:music or date:yesterday and more as described in Specifying criteria in the Spotlight search field

I always forget about these and instead use the search window to build up a boolean criteria rather than use the default spotlight menu search (where all the other data detectors compete to provide you relevant matches)

Instead of command+space try option+command+space

Then click the circle + on the right by Save and override the "Any" with "Folder"



I don't know a way to automate or save this further as the default, but it's a way that will work on all Macs.