Calvariae

It seems as if they typically spawn at about the same altitude - which is usually underground - but in ocean biomes they spawn under the water and in plain view. Also they have glowstone on their ceilings, and while not directly viewable from above, the light helps when trying to spot one. These structures are completely enclosed, so the fact that they're underwater makes no difference; it just makes them easier to find.

It's from the 'Dungeon Pack' mod. I've ran across several of the floating houses as well as a barn, a HUGE pyramid, a graveyard, some keeps, some boats/life rafts, a few obsidian towers, and several underground maze-like structures. Those mazes are stupidly common/easy to find around ocean biomes. Also I came across an underwater netherbrick castle - though I guess it could spawn on land too - that had some blaze spawners as well as a ghast spawner. Official MCF post: http://www.minecraftforum.net/topic/1340914-152smpbukkitforgedungeonpack24-dungeons3-bosses2-npc-villages-minecraft-152-ready/

This forum post might help you: http://www.computercraft.info/forums2/index.php?/topic/3728-mc-152-cc-152-immibiss-peripherals/

After I beat the ender dragon I went around collecting ore, but couldn't find any eximite; turns out it was disabled in metallurgy's config files. Is there any particular reason for it to be disabled, or was that just an oversight? Edit: Also Desichalkos was disabled as well. Edit 2: Nevermind, figured out that nether metals was only installed for the meutoite; still, I'm going to try to fiddle around with the config files so that meutoite spawns in the overworld and end and eximite only in the end.

My mistake, I thought Metallurgy was 1.5. Though according to its developer it will (hopefully) be updated soon: https://twitter.com/rebelkeithy

Play tekkit classic or wait for E3 to eventually (possibly) add those items back in. Though, Ender Bags and chests can essentially take the place of alchemist bags and chests. As for condensers, those are permanently gone from Equivalent Exchange; you'll have to learn to use minium/philosopher's stones.

I think the maintainer is trying to make the 1.5 jump, but has to wait for red power. At least that's how I understand it. Though if we're being completely honest, big dig will probably have to abandon rp sometime in the near future. And afaik, ore frequency is being altered with metallurgy's config files, but as to how you could alter it in vanilla/tekkit, I have no idea.

I made the mistake of placing one-way glass on a marble brick and it crashed my game as well, and like BlockBlocksx I wasn't able to reload my map. However, I increased the ram usage via the launcher from 1gb to 4gb and my map was finally able to load. After it did, the one-way glass acted as if I had placed it on sand and I was able to destroy it. 4gb was probably overkill, as task manager only showed java using 1.2 - 1.4gb, but hopefully this'll help anyone who is having trouble. Edit: Also it might be a good idea to make periodic backups of your world save. Just in case something like this happens again.

I used to have a problem like this a while ago. I fixed it by installing 64-bit java - as simply increasing the ram usage via the launcher didn't help. Though, if everything is working for you now don't worry about it.

I was thinking that same thing today as I was walking through the nether. Also, I think metallurgy2 has some nether ores that aren't in the game and I'd love to see them get added too.