You could argue there isn't much design to these, but I find Wiha's line of insulated wrenches simply beautiful as objects. Sized for imperial or metric, they've got open-end wrenches in both stubby and regular lengths, the former for working on underground lines:
Deep offset wrenches:
And insulated adjustable wrenches, which do have some design to them: Because there's no way to insulate the moving jaws, they've shaped a hilt into the handle, to encourage the user to keep their fingers behind them while turning them.
They almost make me wish I was an electrician, so I'd have an excuse to handle these.
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