On Monday, June 2, 2014 12:06:30 PM UTC-7, Bob La Londe wrote:

... He mounted a jigsaw upside down to a small table with
the blade sticking up through a hole. Much like the cheesy table saw
adaptations we see using a circular saw. I don't know how safe it is

I've done that. For thin material (1/4" plywood) it gives good control
and excellent cut visibility. In a pinch, just clamp the saw in the
vise, lock the power switch, and go! I use a power strip, the
cutoff switch there serves in an emergency.