This plug-in can easily convert every colored image (in an html page) into a B&W greyscale image. Read the plugin API on here http://gianlucaguarini.github.io/jQuery.BlackAndWhite/.
1 Include the plug into the page:
2 Set the image wrappers using the css:
3 Initialize the plug in:
the script works only for the images hosted on the same server in which the page is loaded!
If you are looking for a lightweight solution, you can use the following css instead, but it's not 100% crossbrowser: