The Beatles N°1 ! \0/ Overwise : Supertramp, AC/DC, Sex Pistols, Led Zep', Beach Boys...
Aerosmith,Jon Bon Jovi, Gun & Roses, Bread,Tears for Fears,Duran Duran, Alphaville, Chicago,REM,the Police Good Charlotte, Green Day,3 Doors Down,Linkin Park,RHCP and many more.......
At the moment it must be:

Lana Del Rey
Veronica Maggio
Florence + The Machine
Hurts
Adele
Sia
mainly: Muse, Depeche Mode, & New Order and for mellow listening: The Green Children & Sarah Brightman
Circa Survive, Dream Theater, Meshuggah, KISS, A day to remember, Gorillaz & Ghost.

Then we also have like Daft Punk, Nas, City and Colour & The Smiths.

Swedish acts: Håkan Hellström, Lars Winnerbäck, Billie the Vision & the Dancers and Dead Swans.
I'd have to go with Within Temptation and Two steps from hell
Too many to mention! Metallica, Ramin Karimloo, and The Ramones for starters. I have a diverse taste. :D
Absolutely loving Foxes at the moment her songs are so good!
I'm partial to some Disney songs but asides from that Birthday Massacre, Pink, and Beautiful South.
Duran Duran, Depeche Mode, Blaqk Audio, The Birthday Massacre, Seether, Mr. Big, Poison, Motley Crue, I have a varied taste in music!
I posted in here before, but I can't remember what I said. It's changed this last year. I use to love Family Force 5, but as I get older I'm liking their music less and less. Now, I love The Classic Crime. I can go days on end listening only to them. They are incredible.
Tie between Metallica and Savatage.
Most definitely Depeche Mode. Besides them I love The Cure, Siouxie & The Banshees, Sisters of Mercy, The Cult, Killing Joke, Rosetta Stone and The Chameleons.
Gosh, this is actually pretty hard to answer because of how many I love. You could say Avril Lavinge, Kelly Clarkson, The Veronicas, Paramore and Cascada to that, choosing one though, I'm saying Paramore. I don't like their newer stuff really but I think I will always have a thing for Paramore after all, they where the first band that I loved, ever.