In the issue search, at the projects facet, you can search for projects. This search currently only returns projects of the default organization, but should return projects of all organizations.
Currently api/components/search without organization parameter only searches in the default organization.
An optional boolean parameter allOrganizations should be added, if it is set, the search should concern all organizations. Specifying both organization and allOrganizations=true in one request should cause the webservice to fail with an appropriate message.