Well I'll put my two cents in here: I don't like to buy anything to help me make HST(half square triangles)
When I am going to make a lot of hst of the same fabric I cut a strip of one color and a strip of another color and sew them together on one long side. Open and iron and then take a square template for what ever size you need and lay it on the seam so two opposite corners lay on the seam. Now cut out the square with a rotary cutter. You can cut out several out of each strip set and then pull it apart and sew the other sides together and do it again.
Because I do alot of scrappy I cut swatches and make a pile of say one dark pile and and one light pile then I start sewing light to dark until I have them all sewn. Open and iron then I go through and cut a square from each set of swatches.
We do hundreds of them this way.
Just my version!