The latest Lee Valley Woodworking Newsletter (Vol. 4, Issue 5, May 2010) has a great article on how Konrad Sauer reproduced a handled badger plane. Badger planes, “generally considered to be Scottish in origin,” have a blade that is both skewed and rotated (about 10°) so the blade exits out of one side of the plane allowing it to cut rebates.
The original, from Ken Roberts (author of books on woodworking and planes), is shown above. It has a cast plane body that was damaged where the blade exits on the side, and also had a broken front bun.
Although it’s difficult to see in the above pictures, the completed reproduction is a metal dovetailed version. The Lee Valley link has many more pictures of the processes and mock-ups Konrad used. He also details his thinking and trade-offs as he worked on this project.