Some of us keep ornamental or food plants and know that the pesky part of gardening is watering the plants daily. Sure the plants need fertilizer every couple of months or sunlight so we place them in a bright sunny spot. But, the watering needs to be done everyday and you cannot count on it to rain everyday. Too much will drown the roots, too little and your plant will wither. For bigger lawns or even farms, people setup sprinklers that turn on like clockwork.
For city-dwellers like us who probably have just 1 or 2 pet plants, are better off with self-watering plant pots. Ikea carries self watering plant pots for about S$30 (pic above). However, I was just at Ikea and didn't see it so I guess stock is limited to certain places only. You have better luck getting your hands on Eva Solo's designer self-watering plant pot at around S$70 (pic below), isn't it gorgeous!
Most nurseries will stock the plastic version below that you fill with water and stick into existing plant pots. Cheap and versatile, good for people with home nurseries or many indoor plants. It's clean and fuss-free but, maybe not the prettiest thing to look at so you should hide it behind the plant out of sight.