well electricity and computer go hand in hand.
but i've lived without that stuff for a while cause of type of 'holiday' thing where i had to live in a shed for 2 weeks at times for breaks between terms and 4 weeks for summer holidays. only light at night was candles and a gas lamp. only hot water was gas heated. funny cause one time the gas water heater blew up and soot flew up in the air. funny but not when ur in the wheelbarrow having a bath. we also had the drink the tank rain water. i mean don't get me wrong tank rain water can be alright, if the tank is well maintain and u got good guttering where it's collected. but we didn't so it tasted like crap and we had to drink it (convince my mum and dad early of to get bottled water but it wasn't soon enough). yea this was my parents idea of a 'holiday', more like hell.
but the thing i seriously couldn't live without would be plumbing. i mean no plumbing = no water and i need my water to live. plus i need my steaming hot showers in the morning otherwise i would never wake up. man those bad bad experiences where there has been no water, god never want to do that again and i can bet u feel the same way.