1. Amazon EC2 spot instances,
http://aws.amazon.com/ec2/spot-instances/
2. Amazon elastic compute cloud (amazon EC2),
http://aws.amazon.com/ec2/
3. Google app engine: Paid apps: Budgeting, billing, and buying resources,
https://developers.google.com/appengine/docs/billing
4. Windows Azure virtual machines pricing,
http://www.windowsazure.com/en-us/pricing/details/virtual-machines/
5. Deutsche telekom confirms new broadband data limits (April 2013),
http://www.telecompaper.com/news/deutsche-telekom-confirms-new-broadband-data-limits-938900