This is way, way too broad for me to ever give a definitive answer too. Instead, I list about five or seven songs (I hope I don't go over that), and instead of it being a list of my favorite songs of all time, it's my favorite song from a certain category.
Favorite currently:
DLZ ~ TV on the Radio. And yes, that Breaking Bad scene has a lot to do with it but on it's own it's still damn impressive. I absolutely love the lyrics, some of my favorites in there, just brilliant.
Favorite Cover:
Hurt ~ Johnny Cash. There is a reason this is my favorite cover and it's not because it's much better than the original version which I do like. No, that can be said about three favorite covers (Peter Gabriel's "Book of Love" and Placebo's "Running Up That Hill"). What Hurt does for me, it does better than pretty much any song I can think of. And this isn't accounting for music when set to videos but just listening to the track itself and nothing else. I've said this before but Hurt is the saddest song I've ever listened to. There isn't a single aspect of this song that doesn't evoke that emotional reaction from me, every part of it seems to be meticulously constructed to make me cry like a little bitch. It doesn't work, I just don't cry during music but it comes the closest that anything ever has and that's impressive.
Favorite song made for a tv show (so, anime):
Call Me Call Me ~ Steve Conte/Yoko Kanno. Okay, I'm not sure who to credit here, Steve Conte is the singer, Yoko Kanno the composer. Oh, and if anyone's bothering to actually click on these, don't worry, it's in English. Anyway, Cowboy Bebop's most praised aspect is probably it's music, actually it is it's music. Not probably, it just is and it's definitely justified. Now, a lot of that has to do with it's implementation (since but several do really stand alone in my opinion and I could easily due a top ten just from Bebop, and probably a top thirty if I'm going by all Yoko Kanno's works like Wolf's Rain (which has the best OST in anime in my opinion). But regardless, this song is the one that stands above, if I was trying to do just a top five of all-time I'd guarantee this would make it on. It's easily one of my favorite songs ever.
Favorite song from my favorite bad:
Masterpiece Theatre III ~ Marianas Trench. Don't worry, I'm not going to be that verbose here as there is relatively a very simple reason behind this one. Masterpiece Theatre is my favorite album ever, and Masterpiece Theatre III is essentially an amalgamation of every single song on that album.
Favorite song from my favorite solo artist:
Eyes Wide Open/
Night Drive ~
Gotye. I can't choose, I love both for different reasons. But um, if you hated Somebody That I Used To Know, don't worry they sound nothing like that. If you loved it, just know it's from the same creative genius.
Favorite song from a video game:
Stickerbrush Symphony ~ Donkey Kong Country 2. Yo, it's Donkey Kong Country bitch!
Favorite rap song:
Mistakes ~ Immortal Technique. Yeah, if I could decide on Gotye I wouldn't have went over. This is a pretty good way to book-end this list and I've been going on for way too long as it (you should never leave me the option to explain myself [I probably would've anyway but it's not a guarantee]) so I'm done. Anyway, I rotate between this and five or six other tracks as my favorite rap song but at the moment I got to go with Immortal Technique's Mistakes mainly for the lyrics which are pure bliss.
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