Useful shell script 🙂
Find files that contain a text string:
grep -lir "some text" * grep -lir "some text" *.php
The -l switch outputs only the names of files in which the text occurs (instead of each line containing the text), the -i switch ignores the case, and the -r descends into subdirectories.
Quoted from: http://snippets.dzone.com/posts/show/505