The Sleipnir browser
is well-known among Japanese technophiles, many of whom value the high level of customization that the browser allows.
At the center of this customization is the ability to select either the Trident or Gecko layout engines for each Web site visited. Trident was developed by Microsoft Corp. and is used in Internet Explorer while Gecko is used in Mozilla's Firefox.
As any user who has changed Web browsers knows, some sites look different or offer different functionality depending on the browser in use. By clicking a small button in the bottom left of the browser and switching between Trident and Gecko, users can choose the best one for the particular site.
Source: Japanese browser maker takes on IE, Firefox | Computerworld