Looks like FlexiScale and Amazon EC2 have a competitor in the computing as a utility war. The company is called GoGrid, and they are offering a similar service to FlexiScale and EC2. They offering computing on demand, like the other 2, but instead of charging per CPU hour, they charge per GB Ram Hour.
A machine with 8Gb of ram is 2x as expensive as a machine with 4Gb of Ram. Pricing has 2 tiers: Pay as you go and Prepaid (like Mobile Phones!). On pay as you go, you pay $0.19 per GB of RAM per hour. You also pay 50c per Gig Outbound traffic, but unlike the rest, inbound traffic is free. Nice touch!
The prepaid plans have contracts set on them per month. starting at $150 and going up to $3500. these include anywhere from 800 hours to 30,000 GB hour usage, between 200gb and 6Tb of transfer and allowance to deploy anywhere from 8 to 100 servers. Fairly big discounts too. Since pay as you go is 19c per RAM GB hour, if you pay monthly, you can get this down to anywhere between 8 and 12c per hour.