The Mac OS X clipboard is infamous for changing the format of bit-mapped images that are pasted to it. These images are typically encoded using a QuickTime Tiff compressor that renders them unreadable on other platforms (e.g. Windows and Linux). This means that Mac users who create screen-shot based Word or PowerPoint documents are not able to view the images in those documents on non-Mac platforms.
Journal of Object Technology
Lyon, Douglas A., "Fixing Apples' Broken Clipboard, with Java" (2008). Engineering Faculty Publications. 60.
Douglas Lyon, “Fixing Apples' Broken Clipboard, with Java”, Journal of Object Technology, Volume 7, no. 3 (March 2008), pp. 17-23