QuickNFO is a simple viewer application for .nfo files.
In contrast to other nfo viewers, QuickNFO does not require font files or anything else to be installed. The nfo text can be exported as HTML or unicode TXT, so it can be viewed on machines that don't have QuickNFO installed (via the File -> Save To command).
In addition, QuickNFO provides a QuickLook plugin that previews the file contents directly from the Finder. It supports both the creation of icon thumbnails and the (space key activated) QuickLook preview. The QuickLook feature is automatically activated if QuickNFO is defined as the default program to open nfo files.