Now, anytime you need to leave home on a business trip or a 2 week vacation, you fill a soda pop bottle or two with the precise amount of water you'd use during one plant watering and seal off the bottle by screwing in a one of these disolvable pellets. You flip the bottle upside down and situate it (prop it) so that the neck is pointed at your houseplant's soil -- perhaps an accessory might be useful for securing the pop bottle in place -- and the time-specific tablet begins disolving. Some tablets disolve in a day, some 2, some a week, whatever... Also, some tablets are made of plant food.

The great thing is that the pellets are small and store easily. In my opinion, having a few small pellets would be better than having to own one more gadget -- some device that periodically waters plants.