XmHTML, a high performance Motif Widget capable of displaying HTML 3.2
conforming text. Amongst it's many features are the following: 
  * builtin image support for X11 bitmaps, X11 pixmaps, GIF87a, GIF89a,
    JPEG and PNG; 
  * GIF images are decoded using a patent free scheme; 
  * builtin support for animated GIF89a and animated GIF89a with NETSCAPE2.0
    loop extension. XmHTML supports
  * all GIF89a disposal methods; 
  * image support covers all X11 visual types and display depths; 
  * delayed image loading; 
  * progressive image loading; 
  * builtin scrolling interface (both keyboard and mouse); 
  * anchors can be displayed as pushbuttons; 
  * anchor can be highlighted for enhanced visual feedback; 
  * autosizing; 
  * capable of displaying text/html, text/plain and standalone images; 
  * supports the full HTML 3.2 standard; as well as the HTML 4.0 <FRAMESET>
    tags; 
  * an extensive set of callback resources; 
  * full text justification; 
  * smart and user-definable font mapping; 
  * can work with a predefined palette (which it can even create for you); 
  * builtin quantizer using Floyd-Steinberg error diffusion; 
  * four different dithering methods allow one to achieve an optimum
    balance between performance and image quality; 
  * HTML Table support; 
  * Support for HTML4.0 Events; 
  * fully compatible with LessTif

XmBalloon, a very lightweight "tooltip" Widget to show a one-line string
in a small popup-window. Features include the following: 
  * Choose between a rectangular or shaped window; 
  * Popup window can be transparent; 
  * User-configurable Popup and popdown delays; 
  * very easy to use;