This is a great idea for a thread, though!

Hmm.... Most hated tool?

For me, maybe an egg beater drill without a horizontal handle for the left hand. If I'm just holding the vertical handle at the end, there's very little to stop the torque of the bit, and it gets really tiring and hard on my tendonitis prone wrists to grip the darned thing tight enough.

Nonetheless, I still find it super useful for drilling really tiny holes with delicate bits that would just get destroyed in a bit brace. In that context, there's far less torque so it's no problem.

The coping saw might be a sorta kinda hated second place tool. It's useful on occasion, but I usually prefer to just go in with saw kerfs and a chisel or spokeshave depending on the radius. It's always a lot of work to clean up after a coping saw, because it's so difficult to keep the cut square and the kerf is always so ragged afterwards.

There are many tools that I hate much more than this, but they're not in my shop