Memory hacking in Linux

I'm looking for a program that works on Linux that will let me view/modify memory locations, preferably one with a not too cryptic interface. I did try googling but I wasn't sure what to look for, any hints?

>>1

void *p = 0xDEADFACE;
memcpy(p, "LOOK I CAN CHANGE MEMORY LOL", - sizeof 1);

>>2
Virtual memory, do you know it?
Enjoy your segfaults motherfucker.

>>1
You would probably have to hack the kernel and add some syscalls (making whole system unsafe)