If you want to tune your upper strings up a lot you could play devin townsend/Strapping Young Lad's post 2004 stuff (he tunes GCGCGCE, I know Alien at least was recorded on a massively downtuned 6 string and thus didn't use the high E). If you want to stay in drop G I'm sure some of his songs are playable without moving off the lowest three strings. Large chunks of By Your Command and Ziltoid Attax, for example.
Jed didn't like using 7 strings. He used the low G on LTD Eclipses. 24.75 inch scale and low G were a pain to tune and think of that guy's picking attack. He used .60 gauge for the low G, same with Dev, but he was playing on an LTD SC607B at 27 inch scale with a .60.
Fear Factory used low G when Christian was on guitar too.