2007+: password cracking on GPUs

Pioneered by Andrey Belenko of Elcomsoft
Initially for NTLM, LM, and raw MD5 hashes, achieving speeds of over 100M per second
Beyond reach of existing software on CPUs at the time (except for Cell)
Andrey and others improved the speeds and implemented other attacks
2010: Whitepixel by Marc Bevand achieves 33.1 billion passwords/second against a single raw MD5 hash on a sub-$3000 4x AMD Radeon HD 5970 computer (8 GPU chips)
2012: oclHashcat-lite by atom does 10.9 billion on a single HD 6990 card (two GPU chips)
2011: oclHashcat-plus by atom made GPUs usable for a full set of password cracking attacks on a wide variety of hashes (both "fast" and "slow" ones)
John the Ripper is catching up with GPU support
2011, 2012: more limited in GPU support than oclHashcat-plus, but Open Source