If I had to list my current favorite bands, they would probably be in rough order:
1. The Pineapple Thief / Pink Floyd (Can't decide between them

)
2. Tesseract
3. Sonata Arctica
4. Tunng
5. Periphery
Honorable mentions: Rush, Led Zepplin, Nirvana, Animals As Leaders, ELO, Porcupine Tree
I think most people have prolly only heard of Pink Floyd or Periphery in my top 5 list, but I recommend all of them. (Periphery does have swearing and violence in their lyrics sometimes, so keep that in mind)
I don't know if anyone else has this, but my favorite songs tend to be ones I don't really like too much at first, but enough to listen to again. Like I think they are mediocre the first time I hear them, but the more I listen to the song the more I like it. Songs I really like the first time I hear them I usually get bored of eventually and then only listen to occasionally.
I love hearing new types of music, so feel free to send me interesting songs! And if you like prog I have tons of suggestions :3
I like many genres of music, but some of my favorite bands are Dream Theater, Serenity, Symphony X, Rush, and Nox Arcana. Progressive and Symphonic Metal are my favorite genres overall, but I've expanded my tastes to include other things like D&B and Ska-Punk.
Dream Theater \m/
[1] Depeche Mode
[2] Def Leppard
[3] Savage Garden
[4] Three Days Grace
[5] Rise Against
Honorables:
Rascal Flatts, The Cure, Bullet For My Valentine, Stray Cats, The Police, Guns & Roses, Alice Cooper, Luke Bryan, Breaking Benjamin, Alice in Chains, Meatloaf, Poison.
Generally, anyone from the 80's, most from the 90's, and a few 2000's. 
Didn't know people still knew who Depeche Mode was XD glad to see another fan. Do you like INXS? Alice in Chains is good too.
(This post was very hard to not make into a huge wall of text)