GtkHTML
GtkHTML is a free HTML rendering engine, which is written in C and uses GTK . The project is a fork of KHTML. It was later developed by Larry Ewing and with the support of Ettore Perazzoli and published by Ximian, before the company was acquired by Novell.
GtkHTML is part of the Gnome desktop environment and is mainly used by evolution. In most Gnome programs, however, the Gecko engine from Mozilla is now used. Currently, efforts are made to implement WebKit itself as a complete alternative for GtkHTML.
In the instant - messaging program Gaim, Pidgin today, briefly came an eponymous, but completely independently developed rendering engine used.