Lemons, preserved or not, are really great for many types of foods from Western to Eastern, stopping by at Middle eastern, so really universal.  Lime is sweeter than lemon and is used more in Eastern dishes but you can interchange them as I discovered if you have one and not the other.  I have been experimenting with lemons and limes recently so here are some of my discoveries and money saving tips.

1. To keep lemons and limes fresh for a long time, do not put them in dishes and display them on dining tables as they show in home improvement shows.  Instead, put them in a jar and fill it with water and keep in the fridge.  This way, they keep for a long time instead of becoming dried and unusable.  Lemons and limes are quite expensive, so this is a good money saving idea.
2. Lemon rinds can be dried at home, before you use the juice for cooking, so try to buy unwaxed limes and lemons and make lemon peels instead of throwing the peels away.
3. It is quite easy to make preserved lemons however, the cost and time required are not worth it, according to me.  So it is cheaper to buy organic preserved lemons than making them at home.  Plus you can buy these anytime of the year- if you choose to make them at home, lemons can be quite expensive in the summer, so you have to wait for winter to make them at home. However, one money saving tip I have discovered is not to throw the fleshy bits as many of the Moroccan recipes suggest and only using the rind. In fact, once you cut everything in bits and discard the inedible internal skins and bitter seeds, you can use everything up. I have so far used these in Moroccan style lamb and chicken; and Italian style pork.  I have used grape juice to sweeten the dish as the lemon bits can be quite sour.
4. Both lemons and limes can be used to make lemonades. I prefer a quick version using squeezed lime and lemon juice and some sugar and a pinch of salt- then mixed with fizzy water and ice. You can thrown in the used rinds and some mint leaves if you have them.  A cheap cool drink for the summer.