What is your most used manually operated Practical Home shop built tool/tools

There have been a lot of useful ideas of home shop built tools and equipment on the site and I would like to see other ideas of other manually operated

So if you have any home shop built tool/s that you use often? No matter how crude or rough in design it may be or how common.

If so and you would be willing to share you design and photos of your tool you built plans, dimensions, materials tooling to build etc.

Anything manual operated from yard tools to shop tools and specialty tool that served you well in the application you designed it for.

Any devices for holding things at odd angels like weed eaters and chain saws for repair to screw jack type liftís and Jigís for line fabrication of any item or product.

Thanks'
CH!