How About:

Pros:
On Backstab, regain 100% cloak

Cons:
When revealed while cloaked, your silouhette will remain for 0.5 seconds longer.

The Pros :

on Backstab , Give U Speed Of The Same Speed When You Get Hit By The Disciplinary Action For 3 Seconds

---------------

The Cons :

Your Speed Will Be Like Demoman Speed , All The Time

The Cloake And Dagger Will Decreases So Fast While You On Speed

Pros:

* On backstab regain 100% cloak

* Instantly cloak on backstab

* Increased movement speed while cloaked

Cons:

* -50% cloak time

* -100% cloak regen

* -50% cloak from ammo packs

i have an idea.
on backstab instantly cloak. now hes here now hes not. spy dissapearing act!
taunt:the spy holds a magician wand up. then he spins it around and gathers magic. then he swings with it. i thinked it would or make the every enemy on your screen spontaneously combust. this does not work in spawn. or while enemies are in spawn. (cause while you are in spawn you must go out and then do it and enemies are in spawn and then they must go out) spy would hold it up while its casting a rainblower-like beam or when he swings it it could launch a random projectile from this list
random projectiles:
flare
rocket
demogrenade
machina beam (non charged. cannot get headshots tho)
rescue ranger projectile
rainblower beam
huntsman arrow
or i thinked spy could spin it around and then when it gathers magic it would shoot a green flamethrower flame that paints everything green (paints a small area green or players green works on teammates and enemies) sort of like a spray paint thing ya know?

How about this?

+/-Upon Backstab, the Spy immediately teleports and cloaks to a random teammate
+This knife has a 40% longer reach(You can stab from farther away)
-The teleport will consume cloak depending on the distance teleported
-Cannot be equipped with Dead Ringer
The main purpose of these stats is to give the spy an instant runaway strategy but also make it near impossible to do multiple stabs in a single go, Very useful versus good anti-spy teams that practiclly instant kill you upon notice

All of the +100% refill cloak & the speed boost is a clean copy of the old Big Earner. I like the cloak on kill.

I think a lot of these posts were before the big earner update.

When disguised:

-Spy gains all the abilities of the class (example: Scouts double jump and speed, heavies health, pyro's fire resistance).

-Mouse 2: Disguise seems to attack but their bullets and explosions do no damage.

- 20% Damage resistance

Passive traits:

- No cloaking at all

- Disguising takes 200% longer.