Self Destruct Rocket
Its a missle, you shoot it, and it comes right back at you. You jump over it, hitting the enemies behind you.
Dont jump, and thats why its called a suicide rocket.
S.P.E Beam
A rare and devistating beam this is. Capible of killing the most of
powerful enemies with a single… I’m just messing with you,
this beam makes silly string come out of Samus; arm cannon.
Now samus can pretend she is a rag doll, has long red hair,
and just have fun!
Single: Shoots silly string on samus
Charge: Shoots silly string at samus.
The Brown beam.
Shoots a brown, stinky subtance at enemies.
Single Shot: Shoots poisonous brown ball
Combo shot: Shoots stream of muddy brown stinky acidic stuff.
lol.
The Laser
A basic beam weapon.
Single: Look at the discription
Materia Beam:
Standard: Randomly uses Fire, Bolt, Ice, Earth or Cure
Charge: Randomly uses Wall, Comet2, Regen or Flare
Combo (Knights of the Round): Casts Ultimate End.
>_> Go FFVII!
Combo beam: combinate two beams.
like if you use plasma beam and the power beam you get the fire beam.
charge: combinate 3 beams.
Combo (super beam): A combo off all 4 beams.
laser wings this alaws samus to fly great dissances with a special upgrade with it that alwos her to hovor.
Sounds good, but on almost all Metroid games all the beams combine after being gathered if you dont disable them.
the laser beam:
standard: shoots a small green beam.
Charge: shoots a blue ball of laser
Combo: (???) fires a red beam untill you drop A and Y
The yellow shot: do the combo and hold down only Y and push A, now it come yellow shot in the red laser, get it?
EDIT: sorry dragon, didnt se your post
Hmm. After hearing the talk of a plasma sword type weapon that lunges I wad forcefully reminded of all the weird and cool stuff you can do with Sword Flying in H2.
If they implemented that (escpecially one that lunges) then it would be even easier to sequence break the prime games 
Anyway, as for my contribution.
Stun bombs.
Dropped in morphball mode and creates a bright flash that will stun all non boss/blind enemies for about 20 seconds. Does no damage just might be useful to get out of bad situations.
Not very original I know, but…
This is one that is being used in my game.
The Plazma Ball,
Do you people know on Metroid Fusion how the SA-X does the screw attack
sliding on the ground? Well now that is possible once Samus has obtained the Plazma Ball. All you gotta do is charge up morphball and then release it.
I know not invisable.
It’s a dark alpha grenchler. 
Dragon: YAY! I’ve always anted to be able to use that move. 
Screw ball:
hold X and until the morph ball shining like the boost ball,then drop it, now samus starting to spinn like the screw attack and when it stop spinning you will be back to normal
lol
_>
That’s an exact duplicate of Dragon’s.
<_<
<_<
when I say normal I mean the suit, not the Morph ball mode and the plasma ball
stay’s in morph ball
>_>
That’s still a duplicate of Dragon’s… >_>
Don’t say duplicate peaz. It pisses me off…Don’t ask why…
…>>
<<…
I’m sorry then. My regrets.
Note: This beam as of yet does not have an official name.
[Cutter Beam]
Standard: Fires a small blob of superheated plasma which cuts at objects or enemies.
Charge: Fires a large blob of superheated plasma.
Charge Combo (5 missles): A swipe with the blob of superheated plasma.
That’s kinda like a mix of the plamsa beam from Metroid Fusion, and Metroid Prime.
As of the name, how bout Dissection beam or peircer beam I dunno…