A dirty microwave, for example, can be easily cleaned with water and lemon. Cut a few slices of lemon and place them in a water filled bowl. Put the bowl into the furnace a few minutes until the water starts to boil.
The steam released will soften the dirt and grease and lemon will deodorize the oven. Once you removed the bowl from the oven, wipe off the dirt with a cloth.

Stainless steel sink can be cleaned using a solution made from two tablespoons of baking soda and one tablespoon of lemon juice. Rub the sink with a sponge then fill it halfway with warm water and grate over some laundry mild soap. Wash again the sink with warm soapy water and then rinse with cold water. The faucet will be washed at the same time with the sink, but if you want it to become brighter, rub it with a piece of waxed paper.

If the shower was clogged because of limescale, you can clean it using lemon juice. Put lemon juice in a bag, sink the shower in this bag and let it stand a few minutes. If after this process some holes remain blocked, use a paper clip to unclog them.