In routing the grooves for some shallow tool trays, I ran into a problem with the edge of the board tipping off the workbench due to the downward pressure of the plane. Because I was working with wood that was thinner than the depth of the plane's fence, the edge of the board had to extend beyond the edge of the workbench.
Using a holdfast was not an option (without some finagling) because it would get in the way of the fence rods, and my dog holes are not lined up in such a way that I could use the end vise.
Geez, if only there were a way to secure the board from underneath.
Aha! Carpet tape (which has adhesive on both sides) to the rescue. It worked great. The only potential problem is leaving the workpiece stuck for too long. That would give the tape more time to latch onto the fibers which might tear when you remove the board. So don't leave for vacation mid-routing.
It worked so well, in fact, that I intend to try this trick when planing really thin boards.
In short: carpet tape now has a permanent place in my shop.