About time someone tried this:

http://it.slashdot.org/article.pl?sid=07/10/22/1851226
http://www.net-security.org/secworld.php?id=5567

Using the "brute force" technique of recovering passwords, it was possible, though time-consuming, to recover passwords from popular applications. For example, the logon password for Windows Vista might be an eight-character string composed of uppercase and lowercase alphabetic characters. There would about 55 trillion (52 to the eighth power) possible passwords. Windows Vista uses NTLM hashing by default, so using a modern dual-core PC you could test up to 10,000,000 passwords per second, and perform a complete analysis in about two months. With ElcomSoft's new technology, the process would take only three to five days, depending upon the CPU and GPU.