It is quite common to see a large electrical port shaped like a lightning bolt on portable game systems, flashlights, and other handheld electronic devices. These outlets are designed to be filled by a Raichu's tail, and trainers of Raichu quite commonly use them in this way on their journeys, especially when at some distance from civilization.
Raichu tails have frequently been described as natural plugs, and this description is not without merit. The long, cordlike tail allows the pokemon to put some distance between itself and the electronic device to prevent overcharging and even maintain some freedom of movement, although Raichu are more commonly used as chargers while sleeping. The lightning bolt end is fairly large, and true plugs are much smaller; oftentimes the tail port takes up half of a laptop's side. Compared to other electric pokemon or the difficulty of carrying around a generator, however, it is by far a superior choice.
Although Raichu are by no means useless in battle, it is for this usage as often as for combat that trainers purchase expensive Thunderstones to make their Pikachu evolve.
