Informaticus

I had a bunch of files containing a certain string "foo" that I'd like to substitute with "bar". That can be done in Linux within seconds. I don't know anything shipped with Windows that is capable of recursively renaming files like rename does.

e.g.  You want to substitute every string "foo" of  your set of PNG images with "bar".

foo001.png
foo002.png
foo003.png
rename 's/foo/bar/'g *.png
bar001.png
bar002.png
bar003.png

If you don't trust your regular-expression skills just add -n after rename to get a list showing old and new filenames.