Cobblers

balls of steel

Courage, audacity.

balls to the wall

With maximum effort or commitment.

bust one's balls

To work very hard; to put in a lot of effort.

drag one's balls across

To exert extreme, often aggressive, power or control over; dominate.

great balls of fire

Expressing great surprise.

grow some balls

To be brave; to show some courage, especially in a situation where one has so far failed to do so.

have someone by the balls

To exercise total control over someone; to be in a position to threaten or extort someone.

lick my balls

Synonym of suck my balls.