I would wish that all those fantasies about using EC2 to 51% LTC were put to rest (to say it mildly). You all seem to think that AWS is a game that anyone can play as much as they want to their heart's wish.
First of all, some simple math. A High-CPU Extra Large Instance has a current best spot price of 0.24$/hr on US-East and produces about 15KH/s with the latest optimized miners. In order to get 9MH/s in order to have a good chance of overtaking the network you would need 600 of those which I doubt you could get on that region by itself, therefore you would have to split them to other, more expensive, regions also.
So assuming an average cost of 0.3$/hr per instance, this would mean 180$ per hour of operation.
Mind you, it would take at least a full 24-hrs to get such a full network started properly, and ensure that it is operational as intended. A small script mistake, a reach of the ceiling of available capacity in one region and the subsequent increase of the spot price, a controller instance malfunction (yes, you need controller instances: think you can just list 600 instances on a command line and find out what is wrong where?), or any other incident, costs a few hundreds of $$$ at this scale.
So actual costs to pull this off are in the range of a few thousand $$$.1.
You cannot just rent more than 20 standard instances or 100 spot (the latter is the most efficient one in terms of costs) without submitting a special Instance Limit Increase Request at: http://aws-portal.amazon.com/gp/aws/html-forms-controller/contactus/AWSAbuse
and then your request will be "considered". You can bet that there are not that many such requests every day so they are scrutinized sufficiently. And you definitely cannot submit a request like this and remain anonymous at the same time.2.
Large customers of AWS and large public traded companies can definitely get this Limit Increase easier, but then anyone doing this from within a company account, cannot do this anonymously and definitely risks a lot of their company's reputation. Just think what would happen when a "smart" rogue reporter breaks the news that "ACME Corp. is secretly involved in crypto-currency wars, aiming to (pick one or more of the following: devalue the dollar/end the Fed/undermine the financial stability of the nation/engage in money laundering/engage in illegal untraceable activities)".
Find me one CEO of such a company that would approve of this. And please BTCExpress, if you disagree with that view, feel free to offer a counter argument, since you have publicly claimed that you did such a thing at SC2 launch.
3. You can of course, create multiple accounts and circumvent these limits, but then you would definitely catch the eye of the monitors as a few hundred instances with similar network footprint would ring several bells at the NOC. I've personally seen that AWS response times when trouble is suspected is very fast (much faster that response to support requests TBH), and you can bet that they will investigate it extensively. Finding proof of the use of multiple accounts to circumvent the Instance limits is not that hard. And when that happens, account locking is warranted.4.
And finally anyone who finds proof that they are getting attacked by an AWS cluster of nodes, can use the abuse form:http://aws-portal.amazon.com/gp/aws/html-forms-controller/contactus/AWSAbuse
which, according to the AUP (http://aws.amazon.com/aup
) can be problems that affect a "System" which would definitely fit to an existing P2P network. Anyone with an exposed public face/company is free to claim this (Graeme of Ozco.in comes to mind as an example).
Stop fantasizing about the dangers of EC2, and about such attacks to LTC or any other chain (I might add "of equivalent network size" in order to avoid misinterpretations). AWS is not child's games, unlike some of the crypto-currency experiments. It's a huge cloud service, run by people who might not be the best in the business in terms of support, but they are very sensitive to the responsibilities that they share with their customers and any liability that arises for them due to the actions of their customers.
On the other hand, it's very easy to use EC2 to LOSE some money in mining. Even with spot instance pricing, it is still not profitable to mine any CPU chain.