Print E=mc² or E=mc^2, by using the right side of this equation
C, 66 59 57 bytes
Ignore the compiler warnings. It should work OK as long as you compile it on a big little-endian machine. This code could probably be made a lot shorter on a 64-bit machine, but I'm unable to test:
main(){long long m=1130224008533LL,c=7,E=m*c*c;puts(&amp;E);}

9 fewer characters thanks to @Adam Davis and @Michael :-)