I recently found the following Cloud Computing Vendor List while researching the web.

Cloud Vendor
Level
Type
Status
Cloud Provider
Notes

3Tera
3
Server
Provider
Backbone
3Teras host solutions and provides software for other host providers

Adobe Air
1
Application
Not a Provider
Backbone
Desktop play

Akamai
0
Server
Not a Provider
Software Based
CDN

Amazon EC2
2
Server
Provider
Backbone

Amazon S3
2
Storage
Provider
Backbone

Amazon SimpleDB
2
Database
Provider
Backbone

Apache CouchDB
2
Database
Not a Provider
Software Based
IBM is involved

Apache Hadoop
2
Database
Not a Provider
Software Based
Hadoop is white-hot OSS enterprise search technology.

Areti Internet
0
Application
Provider
3Tera

Box-Net
1
Storage
Provider
Backbone

Cassatt
0
Server
Not a Provider
Software Based
Utility [...]