The infamous carbon snake:
Granulated white sugar and concentrated sulfuric acid, stirred vigorously in the fume hood.
H2SO4(catalyst) + C12H22O11 → 12 C + 11 H2O
H2SO4 → H2O + SO3 as a result of high heat produced.
The end result was brittle and crumbly, and smelled of caramel and acid (a strange and worryingly-enticing combination).