% ls -al
total 12
   4 drwxr-xr-x    2 notme     notmygroup         4096 Mar 17 11:12 ./
   4 drwxr-xr-x  101 me   mygroup        4096 Mar 17 11:12 ../
   4 -rw-rw-rw-    1 me   mygroup          42 Mar 17 11:12 foo.foo

% rm foo.foo
rm: cannot remove `foo.foo': Permission denied

% sudo chmod 777 .
% rm foo.foo