Wobbly Table

[ThomasTheTankEngine]

Carefully pour petrol on the offending table leg and burn it down to size.

 

[ShaolinDreams]

Hit the floor with a sledge hammer where the longest leg resides.

 

[Bennie-Mac]

Replace your floor with sand. YOU'RE WELCOME.

 

[Wossi]

4 beer mats, 1 under each leg. This is always guaranteed to work for some reason.