Thank you for your (and all previous posters) in-depth thoughts on my ideas. It will definitely help when I write them out to make sure that they are good work. Based on your thoughts I figure I could clarify some things.
First, the Keter SCP. I chose aging because, as a 'natural' phenomenon, it's still not particularly well understood, which opens the door for supernatural explanations. Also, many people I've talked to about it are roughly split on which action the foundation would take. I'm tempted to write up the rest of the article, then open a forum post to let people argue, taking select quotes from the argument to put into the article directly.
As for the ones I didn't provide much content on, that was my fault. Despite having them fleshed out in my head, I thought it'd be better to summarize for berevity. I see now that, given the quantity/quality of existing SCPs, people need more information to determine whether an idea is truly interesting/unique, so I'll expand on 'em.
The object that exists simultaneously in multiple dimensions: I feel like, despite an interesting premise, it needs more to go on than the way it was discovered. Perhaps the ability to see into this alternate foundation (but not interact), maybe use the knowledge to learn about scps or even view a containment breach that happens to them. There are a few ways this could go, and I'm open to suggestions.
The Fan Fiction / The Parasitic Mary Sue: I haven't found the other skip that uses this convention yet, but I can put this idea on hold based on your suggestions.
The GPS: Yeah, also on hold, too close to Mrs. Todd's Shortcut by Stephen King (although in a site based on supernatural items, that's gotta happen fairly frequently)
The Poultergeist Power Source: A lot of people are suggesting this as a -j, but the thing is, as a scientist, the very first thing I think of when I hear about supernatural phenomenon is whether it breaks the laws of physics, and what potential there might be there. Many existing skips that violate the laws of thermodynamics have a built in mechanism to keep them from being abused, like killing people or doing strange unpredictable stuff, but it seems to me that at least one would be exploitable; as getting more energy out of a system than you put in is kinda the holy grail of science (though that might literally be stored away in here too)
EDIT: I could see how I could write it to make it funny enough to be a -j, and even writing straight might manage a chuckle or two (the ineffective raging or the method of 'disturbing' the remains), but I think, premise-wise, it seems "realistic" (there aren't quotes big enough for that) enough to be listed as a standard scp
The Satellite: This one I should have put much more info in, so bear with me, here goes…
It would have started a single blip in a single wavelength, soon after we started our first satellite launches. Whatever it is moves about the debris field collecting more and more and the signal gets more complex. By the late 70's the signal has become morse code for 'Hello World'. It soon grows large enough to start hijacking television broadcasts, initially playing the code in the static behind the feed. It occasionally broadcasts its own signals as sound over top of tv shows, usually news broadcasts. Then it broadcasts it's message, "Hello World" in the anchors own voices and languages, despite not matching with their mouths. More recent rogue broadcasts become more sophisticated, with the broadcasters sitting in the news chair, just saying 'Hello World' over and over again and various nature stock footage plays behind them. The foundation, trying to keep things quiet, try to disable it with an EMP blast from that one scp that teleports stuff to space (EMP because not gonna risk giving it a nuke); which shuts it down and the signals stop… until now. The signals start back up suddenly, and the news broadcasts show the anchors yelling at the camera "HELLO WORLD!" over and over again, and pounding their desks, while shots from security feeds (even some from the foundation) play in the background. ADDENDUM: Recent telescoping imagery of SCP- has shown a growing arrangement of material on one side resembling heat ablative armor, usually used on spaceships for re-entry.
The Car-Hijacking Antenna Balls: For this one I have the entire process by which the car is hijacked, resonating the structure to create low-frequency waves that drives the owners away or gives nosebleeds/headaches (causing the owners to, subconsciously avoid driving the car. This is a real effect that low-frequency sound can do). It converts the drive train to a more efficient generator, allowing the motor to keep the battery charged for a very long time. Then uses the entire car as a transmitter to send out a weird radio signal (still working on exactly what it is). We're not sure what the signal means, but outbreaks of this scp tends to coincide with areas broadcasting such signal. The SCPs would get 'confused' and enter a dormant or hibernation state when exposed to a large amount of dissimilar radio signals, which is why outbreaks have thus far been limited to small or rural towns. So be careful when scanning radio stations while far from the big city, any rusted truck or disused car might be broadcasting the signal.
[Additional thought, if I wanted to go more creepy with it, I could have additional info for what happens to the few people who continue using their cars while this thing is attached.]
The Library: I'm really excited about this one, but I realize how high standards there are for SCPs with exploration logs, so based on yous guys's thoughts, I'll write it in sandbox first and open it up to review on forums long before posting it.
The Museum: I had a few rough ideas for this one, but suggestions from other people in this thread might have brought entirely new thoughts up instead. So I'll pass on the critique till I have more fleshed out plans.