I have seen a number of hints about limiting Spotlight search results to filenames only.
If you want to use Spotlight to find a file or directory that has abc in its name, simply type "abc" (including the quotes) in the Spotlight search box (Command-Space), and your search will be limited to file or directory names only.
[robg adds: I was pretty sure we had already run something along these lines, but I couldn't find it when looking through all the Spotlight hints, so here it is -- please let me know if you do find it to be a duplicate. This handy trick will not work for Finder searches, only Spotlight menu searches, so you'll have to use some of the other hints to change the Command-F behavior.]

