Topaz Labs has released B&W Effects, a Photoshop compatible plug-in for converting images to black-and-white. It can also be used with Apple Aperture and Adobe Photoshop Lightroom via a free software add-on called Topaz Fusion Express. 

B&W Effects includes a wide variety of preset looks as well as controls for adjusting tonality, adding grain, and other effects commonly used in black-and-white conversion.

The plug-in is compatible with Photoshop CS3-CS5 and Photoshop Elements 6-9 running on Windows XP or later or Mac OS 10.5 or later. 

Until September 18, 2011, B&W Effects is available for US$29.99. After that, it will cost US$59.99. A free 30-day trial (registration required for full functionality) is available for download.