WCF return types
What is the list of valid WCF return types? I know some but I want to know all of them:

- Primitive types (string, int32, etc...)
- Complex types with DataContract or Serializable attributes
- Stream
- Message
- SyndicationFeedFormatter

void? POCOs?
WCF return types
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What is the list of valid WCF return types? I know some but I want to know all of them:

- Primitive types (string, int32, etc...)
- Complex types with DataContract or Serializable attributes
- Stream
- Message
- SyndicationFeedFormatter

void? POCOs?