OGNL
Camel allows OGNL to be used as an Expression or Predicate the DSL or Xml Configuration.
For example you could use OGNL inside a Message Filter in XML
<route> <from uri="seda:foo"/> <filter> <ognl>request.headers.foo = 'bar'</ognl> <to uri="seda:bar"/> </filter> </route>
You could use OGNL to create an Predicate in a Message Filter or as an Expression for a Recipient List