How about using a full version of NTFS DOS (one that lets you write to the hard drive - assuming the computer is using NTFS) and then installing a DOS-based keylogger while putting a reference to it in the autoexec.bat? Do you think that would work? Is there any other option on the hardware keylogger besides paying $90 for one?
And on a brigher note, my l0pht crack 3 only has 80 days left on the crack! Good thing no one ever changes their password more than once every 3 months ever!