Speaking of hot coffee when the power goes out -- GAS ONE Portable Gas Stove There are less expensive versions that use pretty much the same design, but aren't stainless steel. I have one and have used it during power outages -- two thumbs up.
These are very handy stoves to have but could be somewhat tricky to get going in the dark (when lights go out) for the uninitiated. i.e. loading the gas cartridge.
If using the GAS ONE Portable Gas/Campingaz type Stove then it will need constant attention for indoor use as it won't have a flame failure protection device.
For bug in emergencies I will be using one of these.
http://www.gasproducts.co.uk/acatalog/copy_of_Double_Burner_Europa_Gas_Boiling_Ring_with_FFD.htmlWith a 15Kg LPG Bottle this will easily give over 1-2 months cooking use.
For long term use i.e. Electricity being out for more than 2 weeks I will also fall back on some
LPG Lanterns. The Latern will consume 85 grams per hour @a light output of a 100W incandescent light bulb, so would give about 1 Months use @ 6 hrs per day.
I will generally always have available a couple of 15KG LPG bottles of LPG stored in these;
http://www.amazon.co.uk/Calor-Provence-Portable-Flueless-Heater/dp/B0045U4O4E/ref=pd_sim_sbs_kh_2LPG bottles have some major advantages over other liquid fuel sources, whereby the energy is converted to modern push button electrical living.
i.e. Storage of Generator liquid fuels, Generator reliability and maintenance, noise of operational use, toxic fumes and exhausts etc.