echo /abc/def/gdjs/dkjfd/kdjf/test.exe | sed s/'\(\/.*\/\)\(.*\)$'/\\2/
echo /abc/def/gdjs/dkjfd/kdjf/test.exe | sed s/'\(\/.*\/\)\(.*\)$'/\\2/

cat << end|perl -e 'while (<>) { $blah .= $_ }; $blah =~ s/REGEXP/\1/g; print $blah;'

echo 123456789 | sed -e 's/123\(.*\)789/\1/g'

find . | egrep -ie '\.(wav|avi)$'
find . -iregex '.*\.\(wav\|avi\)$'