Hello, hello, hello.
After having messed with angles in mugen, I couldn't help but waste my whole night thinking in normals, vectors and so on... I almost lost my sleep due to that... :P
So, the first thing I did today as I got myself to my computer was to program a code for aimed projectiles based on the calculus of a normalized vectors.

So, here is the code :P:

;Finds the X component of the vector Player, EnemyNear
;Formula to find the components of a given vector AB
;V(x) = B(x) - A(x)
;V(y) = B(y) - A(y)
[State 1640, X]
Type = VarSet
Trigger1 = 1
fvar(13) = (EnemyNear(0), Pos X - Pos X) * Facing ;Adjust the direction towards player facing

;Finds the Y component of the vector Player, EnemyNear
[State 1640, Y]
Type = VarSet
trigger1 = 1
fvar(14) = (EnemyNear(0), pos Y - Pos Y)

;Finds the vector length
;Formula of the length of a given vector AB
;|AB| = (AB(x)^2 + AB(y)^2)^1/2
[State 1640, Vector Length]
Type = VarSet
trigger1 = 1
fvar(15) = Exp(0.5*ln((fvar(13) * fvar(13))+(fvar(14) * fvar(14))))

;To find the normalized vector one has to use
;the following formula:
;Normal(AB) = V(AB)/|AB|
;So, you divide the X and Y components of one vector by it's length
;Obs:
;Normalized vector = The normalized vector of X is a vector in the same direction
;but with norm (length) 1.
;Now that we have the normalized vector, we multiply it by the desired absolute velocity,
;such as 5 pixels per frame.

;Projectile
[State 1640, Projectile]
Type = Projectile
trigger1 = animelem = 2
projanim = 1010
projhitanim = 1020
projremanim = 1020
projremovetime = 240
projpriority = 1
projshadow = -1
projsprpriority = 2
projid = 1000
offset = 0 ,-35
velocity = (Fvar(13)/fvar(15)) * 5.0, (FVar(14)/fvar(15)) * 5.0 ;Normalizes the components
;and multiply by the desired absolute velocity.
attr = S, NP
hitflag = MAF
damage = Floor(((3 + (3 * Random/1000.0)) * Fvar(28) + 0.5)), Floor(1 + (Random/1000.0) * Fvar(28) + 0.5)
animtype = Hard
guardflag = M
pausetime = 0,12
sparkno = 1
sparkxy = 26,0
hitsound = 5, 2
guardsound = 6, 1
guard.sparkno = 40
ground.type = High
ground.velocity = -2.4
ground.slidetime = 12
ground.hittime = 12
air.velocity = -2.4,-4.5
air.fall = 1
air.recover = 0
ignorehitpause = 1
getpower = 50, 75
givepower = 20, 30

Well, now I have to find the next funny formula to code in mugen... :P

kisses.