I have one for a majority of situations...
Sadness-White tower (David Zoellner on Soundcloud)
Happiness-Pinnacle (David Zoellner, AKA Arbiter 617)
Competitive-Panther (Armored Core 4 OST)
Goofing off-Fruity short 12 (David Zoellner, again)
Smitten with love-Ain't that a kick in the head (Dean Martin)
Awesome-Tex theme (Red vs. Blue revelations OST)