[windows] What are good grep tools for Windows?

If none of the solulutions is quite what you are looking for, perhaps you could write a wrapper to FindStr that does exactly what you require?

FindStr is pretty good anyway so it should just be knocking a GUI up (if you want it) and providing a few extra features (like combining it with Find to find the count of files which contain a specified string [mentioned above]).

This, of course, assumes you have the requirement, time and inclination to do this!