How do i heat something up with no microwave?

i bought a hamburger at mcdonalds for lunch. i put it on my desk in the dorm. i forgot about it because i realized i lost my wallet and had to run out to go find the wallet. and i forgot about the burger. then i went out with friends . its cold now from being on my room temperature (cool) desk so long. if it wasnt 2 in the morning i could use the microwave that the RA has, but he is asleep. so how do i warm it up.