Adobe has released an early version of it's new 64-bit Flash player code named Square. According to this article on cnet, the download is available via Adobe Labs but note however that if you install Square, you'll have to manually update it on your own.
It's an important move for Adobe as it fights competition from emerging technology such as html 5. Hardware manufacturers have been gradually moving away from 32-bit technology in favour of the speedier 64-bit architecture but software has lagged behind in leveraging the technology. Square is said to take advantage of a computer's graphics chip power, in particular when paired with Microsoft's new Internet Explorer 9 (beta) promising a faster and more responsive user experience with Flash-based content.