Just watched 8 Mile so I thought I'd break it down for you all
Yo yo, spin that sh_t

Sprocket:
Sounds funny but don't knock it
You'll lose it all if you don't lock it
and without one you'll just walk it
but when you're fixed you will rock it
like a power plug in a socket
put them greens in yo pocket...

Cog:
Like a lyin witness in the docket
ain't no matter how you talk it
on the street you cannot hawk it
and the fixers will just mock it
till in the end you will say fock it...

word.