Mox Doubler, also makes your Lotus/LED tap sac for 4.

makes chromatic sphere/star, as well as the original odyssey eggs, mana neutral.

Arcum's astrolabe becomes a snow sol ring that does not cost a card. There are a fair number of artifacts that benefit from this, though I don't think you need look too much further than what we already have.

Getting to 7 mana and using the activated ability can put emrakul or griselbrand into play. I have to believe putting Gris into play, drawing 14, then knowing all your mana rocks produce 2 has to be game over.

Infinite mana with basalt monolith. cute

Does not add to LED fyi, LED does not tap, it just sacrifices.

Also worth noting that it also does not add to Urza mana.