Opie is a mature, Unix-like login and password package installed on the server and the client which makes untrusted networks safer against password-sniffing packet-analysis software like dSniff and safe against shoulder surfing.
It works by circumventing the delayed attack method because the same password is never used twice after installing Opie.
OPIE can restrict its logins based on IP address.
OPIE can improve security when accessing online banking at conferences, hotels and airports.
OPIE shipped with DragonFly BSD, FreeBSD and OpenSUSE.