Another common symptom is presure and coolant releasing thru the radiator cap. Most caps are rated for around 15 psi. Presure in cylinders escaping into cooling system will be a lot higher than that.
Most fun (?) symptom is when it gets really bad and you go into hydraulic lock. This happens when the cooling system has been presurized and you shut off the engine. If the leak is bad enough, coolant will be pushed back into the cylinder where the leak is. Then you try to start the car and of course you can't compress a liquid. Engine turns then stops. Only way to get it to turn is to remove spark plugs and let coolant gush out. Had exact thing happen on buddy's BMW 320 (The Ultimate Repair Machine). Lemme tell you, a half litre of antifreeze can get you awfull wet! Don't be a dumb*** like me and stand in front of the open spark plug hole.