First Appearance: Super Metroid (1994)
Despite not appearing until the third installment of the series, the Charge Beam has become synonymous with the standard Power Beam as Samus' staple attack. It has been available either as an obtainable powerup or part of her starting arsenal in every game since it's debut.
Speaking of the Prime series, once you've located certain powerups you are able to fire a combined Missile/Charge Beam attack based on your current Beam selected. These drain your missiles like crazy, but are extremely useful.
In Super Metroid if you have a single beam equipped, the Power Bombs selected, and charge a shot, a special effect will happen based on your beam (the Wave Beam launches powerful beams in four directions, Ice creates a circular shield, etc.)
The Charge Beam also makes an appearance in Super Smash Bros. as Samus' main B attack. It takes a bit to power up, but if you hit somebody with it, they're done.
The Charge shot is perhaps Samus' iconic attack, and that's not going to change anytime soon.
6) Power bomb
The Power bomb is great for destroying large portions of the environment. I love setting one of these and watching the floor fall out from beneath you, or a wall disappear. I just really like this weapon. Unfortunately it doesn't do much against bosses. Either way the ability to blow up large amounts of the environment is great, and that's why the power bomb is my number 6.