So far, I've mostly written about cooking, but the blog has other useful things in the title as well.
Every now and then, there's leftover tea in the pot, it's gone cold and you don't want to re-heat it in the microwave oven. Why throw it away?
Pour it on your plants, they love it. The same goes with coffee. That's assuming you haven't put milk in either, that'll just go off and make your house smell badly, but as long as it's pure, the plant's will love it.
The same goes for regular fizzy drinks, not diet/light varieties. If a large bottle has been open for too long and the fizz has gone out, and hopefully there's not too much colourings in it, the plants will love some sugary liquid.
Of course, you still need to water them with water.
I know some people actually put the used tea leaves/coffee as a mulch ontop of the soil in the pots, but the few times I've done it, it has gone mouldy and unpleasant, so I compost it instead.
If you use a can with a filter for your drinking water, the first two lots of water filtered through a new filter are also good to use on plants, and I have a 6 pi milk bottle that I use to store this water in, should the filter change not coincide with plant watering time.
If you are really ambitious, you'd save the water you run from the tap and shower, while waiting for the hot water to come through. Thinking about it, that's quite a lot of water being wasted. And there are good types of washing-up liquid to use, so the washing up water can be used on the flowerbeds too. This one is not recommended for the vegetable and fruit garden.
Other things to do is to switch off the shower, while soaping in, and switch off the tap while brushing your teeth. And not having the tap running on full, in order to disguise noises!