grep --exclude/--include syntax (do not grep through certain files)

grep -Ir --exclude="*\.svn*" "pattern" *

Linux : search and replace string in a directory recursively

find /home/zana/folder -type f -exec sed -i 's/oldstring/newstring/g' {} \;

find . -type f -print0 | xargs -0 sed -i 's/Application/whatever/g'