At first blush, it's hard to imagine ARM as much of a threat to anyone. It's a pretty small operation -- certainly not as big as you'd expect considering its customer list. ARM's 1,700 employees make it about one-fiftieth the size of Intel and a tenth the size of AMD (AMD, Fortune 500). Its annual sales are $397 million -- less than Intel makes in a bad week. But these details obscure a few important factors: ARM's no-frills business model, its lead in power-efficient technology, and its ability to help customers make unique gadgets.