Kind of a four way tie for me...
ELO
youtube.com/watch?v=yCUm2GthNJs
youtube.com/watch?v=BeRcOqieEio
Sabaton (Even more epic if you know your WWII history)
youtube.com/watch?v=nhI4NwEqUE0
youtube.com/watch?v=21Uqy2YjuP4

And one more I almost forgot from Sabaton again-
youtube.com/watch?v=hbw1pGUhG7Q

I fell in love with caravan palace, a french group with a electro swing style

[b]watch?v=h_zSkOpi3BE

[/b]the electro swing the better music style of 2013

Also, C2C (a french group again :D)

watch?v=tvY7Nw1i6Kw

P.S: The french are very good in composing electro stuff :d.

Best Song I've ever heard? Probably has to be Forever Autumn. I just think it's such an amazingly beautiful song. However, it is joint first place favourite with these:
Saviour - Black Veil Brides
Saviour - Awaken The Empire
As The World Falls Down - David Bowie (from Labyrinth)
and
Story of My Life - Juliet Simms
All of them just feel so strong and meaningful to me in their own individual ways, and I honestly love them all equally. They make me feel better at any point in time, each one helping with a different emotion/feeling/struggle.
Though not at all the best song, or one of my favourites, I do think that Hocus Pocus - Focus is an absolutely fantastic track too.

Either:

Wolfgang Gartner - Love & War
Savant - Wildstyle
The Living Tombstone - Dubstep Dishwaster
Gorillaz - Clint Eastwood
Gorillaz - All Alone
Gorillaz - Feel Good Inc.
DirtyPhonics - Dirty
Borgore - Decisions
Imagine Dragons - Radioactive

Yeah, that's it.

My favorite song is

Seek And Destroy-Metallica
Take over-Evanscene
My Generation-Limp Bizkit
My way-limp bizkit
The Game-motorhead

lift me up unstoppable and love dont live here by twiztid

BT - Skylarking or maybe deadmau5 - Strobe

It is hard to choose, but here we go.

This is the one.

Noriaki - Unstoppable
swag

Hey Dude!!!
First of all, I want you to know that im a keyboardist so i like listening to Dream Theater.
Oh, also make electro music using FL Studio, so I like Skrillex too!

W-B-X by Takuya and Kamiki Aya
A Little Less Sixteen Candles by FOB (son of a bitch song keeps reminding me of my crush/es)
Xtream Dream

And more

The Birthday Massacre's "Play Dead" is probably my all time favorite song. I can relate to the message in the lyrics and the music fits just about every mood I'm in.

Definitely "Remembering Sunday"
youtube.com/watch?v=NxWiFla_8-I

All Intros and Outros of Soul Eater

youtu.be/9tIltpCXrKI

Hehe Black Eyed Peas-Pump it :p youtube.com/watch?v=ZaI2IlHwmgQ

Blackened by Metallica has got to be the best song ever written.

Just give me a reason by Pink Feat Nate Ruess.

Hands down (at least for me :3) Avenged Sevenfold - Gunslinger