Before trying to compile and run any of the toolkits below, keep in mind that they're all in progress and at most at the prototype stage. And Wayland is still in development and the API and the core protocol is still changing. We try to keep things up to date, but you're likely run into breakage.
Wayland support in the Qt 5 toolkit is happening in the Lighthouse wayland plugin. To try it out check Qt 5 Wayland instructions.
With GTK+ 3.0, GTK+ gained support for multiple backends at runtime and can switch between backends in the same way Qt can with lighthouse. The Wayland support is on the upstream GTK+ master branch but disabled by default. You can find full details in the GTK+ Wayland instructions.
The Clutter toolkit has a Wayland backend that allows it to run as a Wayland client. The backend is in the master branch of the upstream repository. You can find full details in the Clutter Wayland instructions.
Benjamin Franzke is working on a port of SDL to Wayland, it's available in his sdl-wayland repo on freedesktop.org.
The EFL port to Wayland is under active development - Ecore, Evas and Elementary have backends that target Wayland for both SHM and EGL based presentation. Full details can be found in the EFL instructions