It's not going to work
From the (very) few times I've browsed the Spiral Knights forums, every time in general discussion, there's a thread with the intent of rallying everybody into lowering the price of CE. I wouldn't know myself, but from all of the words flying around, apparently the current prices are outrageous, and need to be lowered.
Let me just tell you guys something: nothing is going to happen.
Sure, you may get a couple of people to follow your movement. I'm not trying to sling mud on that. What I'm trying to get across is that the CE market isn't changeable with just a couple of people. It's like a major political movement; nothing will get done unless enough people back it up.
The CE market is a player-based economy. I've played my fair share of MMORPGs with player-based economies, and in every single one, there are people complaining about things being overpriced. I don't understand why you guys keep pointing your fingers at OOO; sure, they may have some dodgy business tactics, but they haven't done anything to the CE market. It's all the doing of the people who have the time and resources to manipulate it.
So yeah.

people need to stop complaining and let the market run it's course, prices rise and fall, there will never be a static price for CE, inflation is inevitable when injecting new currency into a market as liquid as this one.
I don't even think it's being manipulated. And really once you get past the early phases 5K is nothing. 100 energy will last you a good hour and return 20K~ crowns in T3. Honestly, 5K for 100 energy seems like a bargain. I'm kinda shocked it ever went down to 3K. A lot of us have stocked up because it was, and still is, a good deal.
If OOO is guilty of anything it's not giving new players enough of a boost to get off the ground and keep them playing. Something like reduced cost elevators while you're new would really help them get moving. The system and prices are balanced for mid-late game but are rough early on. If anything OOO sees it as an incentive to spend a few $ to get over that hump.
Really though there's nothing you can do. It feels good to vent and try but it won't accomplish anything. The systems not so bad that you could get massive amounts of people to support the cause. I think most people understand that if you want to progress at a nice clip and play as much as you want it will require a bit of an investment. You can get by without it, it will just be slower and somewhat of a hassle. People who spend even a little on the game don't really notice a problem and so long as they're happy and continue to spend a little then OOO is happy.

There are two ways the CE prices will fall. It will happen if:
1) the people who buy CE with real money decide to lower the prices for everyone else.
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What I mean by the statement above is that a lot of people who buy CE with real money would have to decide to sell the CE back to the playerbase for less crowns then it's selling at now, thus reducing reducing the price of CE for everyone.
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2) A bunch of people brought CE and sold it back on the market at a loss.
I doubt the former will happen because people value their money. I doubt the later will happen because CE is important in game and no one wants to sell it for less than it's worth.
CE prices did fall at one point. It fell when we had the player surge from steam. But the CE market has stabilized now that the newbies are becoming late game players. I doubt we'll see a lowering of CE prices unless we get another player surge.
The people who buy CE with real money don't 'decide' the price by joint agreement for the same reasons that the people who buy CE with crowns don't. You can't get 100% unanimous action and cartel style control with an open and uncontrolled market. So '1)' is as unlikely as the things the OP is complaining about.
Other things can happen to change the market, so the list could go on...
3) Three Rings adds enticing crown sinks.
4) Three Rings lowers crafting costs or other CE sinks.
5) Three Rings increases elevator costs.
6) Three Rings has a promotional event where players get a bonus item when they spend real money.
etc, etc.
Of course none of them start with 'the players band together'.
But then again, in each of the threads calling for CE buyer solidarity and joint action, it's already been pointed out clearly why you can't do this, but some people simply don't want to hear about how markets actually work so they keep trying the impossible.

The people who buy CE with real money don't 'decide' the price by joint agreement for the same reasons that the people who buy CE with crowns don't. You can't get 100% unanimous action and cartel style control with an open and uncontrolled market. So '1)' is as unlikely as the things the OP is complaining about.
I agree with this completely. I didn't mean to imply that there was some type of cartel control on CE prices. What I meant is that each player who buys CE with real money decides what to sell their CE for. Together, each paying player's individual decisions set the price of CE for the rest of us (if I understand the system correctly... I might not. Yes, some people can try to snatch all the CE away and inflate the price, but it's unlikely that a few people will buy up all the CE and sell it at at a reduced price...)
Anyway, If a lot of people suddenly decided to sell CE for less crowns then it's currently selling for then the price of CE should go down. But, chances are people will not do this because real money is valuable and CE is valuable, so why sell it at a low price? That's what I mean by number 1 in my previous post. I'll go back and edit my post to make it a bit clearer. (:
It doesn't really matter what price people -want- to sell their CE at. If someone buys $19.95 worth of CE and sells it all, they're going to fill 75 orders and push the price down by the same amount when all is said and done.
If they do it in a dramatic market-pushing-down fashion someone else will profit from it - most likely players that are buying low and selling high, but perhaps a few blocks would go to a lucky player that uses it directly. It doesn't really matter though, by the next day. Whether or not a player tries to sell at the highest possible value or goes ahead and undercuts the market, the amount of cash-bought CE put onto the market eases demand by the same amount, and the tension between crown-buyer demand and CE-seller supply is what finally determines price.
(Well, and also the perceived value of crowns which is pretty low since they have very little use and are in enormous supply.)
The CE threads will keep coming and they wont stop coming.
Vicious circle man, so sit back, relax, and enjoy the game the best you can.