Low bandwidth mode?

I travel sometimes and end up tethering to my phone, even though it is unlimited 3G with tethering i prefer to keep usage down, especially as some areas have quite low speeds (1-2Mbps).

As i understand my macbook air has all sorts of background data transfer checks etc, from simple email checking, apps update checks, icloud background transfers etc.

Is there any easy way i can just disable these or am i best just to create a new account with no accounts set up?