Your favourite character lines.

[lolzorz]

Scout: dis map ain't big enough for the two of us!

Soldier: This is not a camping trip Sheila, this is war!

Demo: Ye're a shame to your people, ya mumblin' devil!

Heavy: YOU ARE A LOOSE CANNON SANDVICH, BUT YOU ARE A DAMN GOOD COP.

Engi: Erectin' a statue of a moron!

Medic: I'M GOING TO SAW, THROUGH YOUR BALLS.

Sniper: Look at me, I've bagged the world's fattest man!

Spy: I'll bury you in the tomb of the unskilled soldier!

[Dirtcopter77]

I love anything said by Scout or Spy, but my favourite lines are

http://wiki.teamfortress.com/w/image...ationhvy02.wav
and
http://wiki.teamfortress.com/w/image...ionHeavy08.wav

Edit: come to think of it, I just like it when people dominate Heavies.

Edit2: Here's a good soldier line too.
http://wiki.teamfortress.com/w/image...nSoldier02.wav

Edit3: Screw it, here's a demoman line.
http://wiki.teamfortress.com/w/image...nsoldier02.wav

[ReaperQQS]

Any pyro laugh makes me feel happy deep down inside...

[stamda]

"HAAAAHAHAHAHAHA! OH-*SNOOORT*-AHAHAHAHA-*SNORT*-ahahaha!"

[Tiamatt]

Scout

"$400,000 to fire that gun, huh? Yeah, money well spent!"

Solly
"I cannot be bargained with! I cannot be reasoned with! I do not know where I am! I am a robot, I don't understand anything!"

Pyro
*sound he makes when he does his fireball kill taunt"

Demo
"Gonna kill you and I'll keep killin' you and I'll never, cause you're 'onna be dead and then I'm gonna kill you."

Heavy
"Look at you tiny-itty-bitty men running from sandvich!"

Engie
"If y'all had more gadgets for killin', you wouldn't need so many for hidin'."

Medic
"Would you like a second opinion? You are also ugly!"

Sniper
"One sniper to another, mate: Give! Up!"

Spy
"Here's what I have that you don't: a functioning liver, depth perception and a pulse!"

[kiriona]

Several of the Tin Soldier lines, e.g. http://wiki.teamfortress.com/w/image...er_robot25.wav, http://wiki.teamfortress.com/w/image...er_robot23.wav, http://wiki.teamfortress.com/w/image...er_robot29.wav etc

Also Scout's line about having such a tiny freakin' head and there are probably a few others that made me giggle.

[MiKeV]

My all-time favs:

Sniper
Demo
Soldier
Heavy
Engie
Medic
Pyro
Spy
Scout

[hdc3r0]

sniper:
"gotcha'! you spastic little gremlin!"

[Genghis Guang]

Pretty much anything the sniper says is gold.

"If your strategy is to build me confidence, it's working."
"Nothing personal, mate, I'm just better."
"Now I gotta make a necklace outta your teeth, bushman's rules."
"You're making this so easy, I'm actually getting worse."
"All rockets, no brains, eh mate?!"
"Aww, did I get blood on your suit?"

And tied for all time favorite:
"You want to hear something funny? You're dead."

"Here's a touchin' story. Once upon a time you died, and I lived happily ever after. The end."

[Crespo_PL]

the robot dominations are magical

[Selgin1]

Engi on dominating a Soldier: "Lift your lid next time and you might see it comin'"

[A 1970 Corvette]

This one.

(I don't even like Demoan that much.)

[Teamfortressguy]

This thing ain't on auto-pilot son!

[SgtFrog]

all the kill lines from the Mini-Sentry!

"Sometimes, you just need a little less gun."
"Heh, I love that little gun!"

[Hartisen]

Dat Snort laugh (classic)
"Ah, that's the stuff!"
"Each and every one of you will be sent home to your momma' in a box!"
Dat Heavy laugh
"Where's your precious Hippo-crates now?"
"Bloody bogan!" (reminds me of VSH)