title: Cross-platform high-level widget toolkits for C
body: <p>Are there any high-level, cross-platform, and abstracted (simple to use) widget toolkits for C that are either very lightweight and fast or can be compiled for other toolkits, such as Qt and GTK+?</p>
  
  <p>EDIT:
  Most C++ libraries lack C bindings, so they will be of little (or no) help.</p>