Citrus: Limes, Lemons, Oranges, Grapefruit, Tangerines, Tangelos

If you are worried about using them up before they spoil:

Cut and juice. Freeze the juice in ice cube trays and then pop out cubes and freeze in plastic bags if you prefer. This is especially handy for lemon and lime juice.

Make marmalade!

Preserved lemons are increasingly popular in American cooking - to make: quarter and layer with sea or kosher salt in sterile jars (use about 1/2 cup salt per 8-10 small to medium-sized lemons. The lemons will sweat their juice - Turn the jar periodically throughout the month (at times it will be upside down) to ensure they remain moist. After the first week you can place in the refrigerator (still turn the jar over periodically). They will be ready to use in 3-4 weeks and will keep for 2 months in the fridge. Use in mediterranean/Middle Eastern-inspired recipes (e.g. lentils); dice finely and add to vegetable dishes; or as a relish for fish or chicken. As a variation - have fun and experiment by adding spices to the jar: bay leaf, coriander seeds, cinnamon stick, chilis.....you're the cook!

Make Limoncello, or infuse vodka or another alcohol with your organic citrus.