xor
little program to xor things, or perform a few other bitwise operations (and, or, shifts). reads from stdin, writes to stdout.
usage
cat /etc/passwd | ./xor -s $'\x01\x02\xDE\xAD'
there's also a test.php that makes sure it works (as i'm really bad at c).
special thanks to whoever made glibc's memfrob() function, even though that *p++ ^= x; stuff ruxed me for like 2 hours.