I finally got around to building a portal in my current world. I'll take a video at some point but right now my world consists of the following:
* Small spawn base at the base of a mountain, right on the water. Flashing redstone torches let me spot it from a distance.
* Attached to the spawn base is an underwater viewing area made of glass. Just for show.
* Also attached is a 12x15 (I think, it's been a while) shaft down to bedrock. To the bottom of that is connected a large area I excavated (only to 2 height, though.) There are also some parallel shafts I did some mining in. I've neglected this area for a while.
* Stretching across the top of the aforementioned shaft is an enclosed walkway that leads to my underground tree farm and storage area. There's also a small "manufacturing" room with a workbench and furnace.
* At the back of the tree farm is another corridor. To the right, there's a vertical shaft with a ladder that goes up to a castle I built at the top of a nearby mountain. It's nothing special right now. It mostly ends up full of animals.
* To the left, there's a tunnel that goes directly to my quarry/castle footprint, which currently stands at (I think) 11 blocks from bedrock. So, I'm almost there. There are some attached caves that I built walkways to so I can still access them.
* Attached to my tunnel that leads to the quarry there was a small cave which I dug out to be a bit bigger and put a Nether portal in. I'll probably enshrine it to make it look nice, or something.
Where I come out in the Nether, there is this awesome lava waterfall directly to my left. Pretty neat.
So, yeah, I'll try to get a video of all this soon...