(Thai Cooking Class, Somi Anuntra Miller & Patricia Lake, Bay Books Cookery Collection)

Roll fruit on flat surface for a few minutes to soften skin. Rub some extra salt on the skin with a little water and leave overnight. (Probably best to put them in a container as the salt leached out a quantity of liquid). Next day boil the water, the 180g salt and sugar for 5 minutes, then cool. Place lemons in sterilised jars and cover with brine solution, seal tightly, and do not use for at least 3 months. Will keep indefinately.

As for what you do with them after 3 months, apparently it's a sidedish, but whether you cut them up or eat 'em whole, who knows.