I have a nice old Wilton 3 1/2" drill press vise, it has a fast action screw and the jaws open to 3 3/4" but are 1 3/4" high so it's kind of too tall for the small stuff I usually have to mill. I tried using a cheap imported drill press vise I got from a yard sale and it was difficult to rely on for a single part and impossible for two, but its very obvious shortcomings made me read about different types of vises.
At the time I looked there seemed to be fewer affordable options. First I checked out Palmgren's low profile vises because they had been recommended for my machine, but decided a screwless vise might work alright, too, and later found some plans for making them. Then I read about pull-type vises on Kurt's website, which work in a similar way. They were way out of my budget but they seemed like something I could make using a nice piece of left over cast iron I had scavenged for making a milling slide for my lathe.
The finished vise is a good size for holding little things - for comparison it's about the same size as the ones for a Taig, and about half the size of the smaller Kurt. I think it works really well.
Step 1: Design
The 3/8"-20 thread is fairly strong and left enough room so I could have a 1/4" hex drive on the end and use a ratchet for tightening it. The screw is centered in the base of the vise and pulls against the end with the fixed jaw, and the moving nut fits in a channel and is angled at the front where it presses against a similarly angled flat on a dowel pin. Clamping pressure draws the jaws together, and pulls the moving jaw and the nut together against the vise body.
What I found from a quick, non-exhaustive search both features seem to have been patented independently in 1951 in the United States by L. L. Walker and L. Pupura but I've seen it advertised that their combination is manufactured exclusively by Kurt.