CSS is the weak content scrambling system used on most DVD-Video titles.
The CSS cryptosystem claims to be 40-bit (for compatibility with United States export restrictions in effect when it was introduced) but actually has some holes that make it effectively 26-bit.
If it is assumed that bruteforcing CSS keys is as fast as bruteforcing RC5 keys in the distributed.net client, then my 333 MHz Pentium II laptop that processes 900,000 RC5 keys per second could crack a DVD in about a minute. Newer versions of independent DVD conversion tools do not rely on the revoked Xing key but instead crack the disc themselves.
Oh, go to jail.