Note: This is just a scene I thought of while listening to Eric Clapton's "Cocaine" today. It could fit anywhere in season three.
Dean tossed his packed bag into the trunk of the Impala, Sam following his lead before pushing down on the trunk lid. Both headed to get in the car, both a little tired and weary, but still ready to push on with a little bit of pride in the fact that they had just saved a girl from a big bad demon that had escaped through the gate. But that knowledge only made them give each other that knowing look; the look that said "One down, who knows how many to go." Dean turned away from Sam disheartened and fired up the Impala. Pulling out of the driveway to the shitty motel they had inhabited for the past week, Dean heard the faint intro to one of his favorite songs and said, "I don't know about you Sammy, but I could go for some Cocaine right about now." Sam just stared at Dean with a horrified expression and all Dean could do was chuckle and turn up the stereo. Dean started singing along,
If you wanna hang out
You've gotta take her out
Cocaine
If you wanna get down
Down on the ground
Cocaine
And all Sam could do was crack a smile and release a relieved sigh (he didn't want a coke addict for a brother) and join Dean in singing the chorus lines of Cocaine.
She don't lie
She don't lie
She don't lie
COCAINE