How about naming the boy one Dio, after the late Ronnie James Dio, who died last weekend(5/16/10). Ronnie had a tremendous singing voice and had fronted Elf, Rainbow, Black Sabbath, Heaven and Hell, and of course Dio. He was diagnosed with stomach cancer late last year and lost his battle with it last Sunday morning. He will truly be missed by us metalheads! \m/
If the other one turns out to be female, you could name her after Wendy Dio, who is now a widow.