When the element boron is mixed with methanol and lit it on fire, it produces a green flame, according to Instructables.com. Since this combination is extremely flammable, it is advised to mix the chemicals in a ceramic bowl, as it can withstand a lot of heat.
To mix the two chemicals, about 1 teaspoon of boric acid (boron in chemical form) is needed, followed by a couple drops of methanol. Green flames can also be created by burning copper, tellurium, thallium, manganese and molybdenum.
Methanol is incredibly dangerous; if the fumes are inhaled, absorbed through the skin or ingested, they can cause death or blindness.