I just added a "How-to" for making Half Square Triangles 4 at a time to MyWebQuilter.com. Click here. Such a time saver!
I also added a calculator to help figure out how large to cut squares when making half square triangles. Enter your desired finished quilt block size. The half square triangle calculator tells you sizes to cut for the 2 at a time and 4 at a time half square triangle methods.