This may sound like a simple idea, but I recently discovered that freezing lemon and lime juice in ice cube trays saves time and energy when it comes to making certain recipes, plus it's great to have for your next cup of tea or hot water!
Freezing the juice from an orange is also a good idea, especially to add to a shake or smoothie, or to put in a glass of red wine for a sangria-like taste!
Freezing herbs like mint can be done as well and is quite practical. I recently planted mint in our garden and began using it in all kinds of drinks and recipes. If you buy mint in a package and don't use it for a while it's very likely to go bad, so to preserve it you can put some leaves in an ice cube tray with water and freeze it. It will be ready for your next cup of tea, hot or cold water, and will make it flavorful and cooler at the same time!
Hope you enjoy!