Does anyone know a good editor for RDF that plays nicely with HTTP

Hi,

I'm looking for an editor that can be used to easily modify RDF resources on the
web without needing to use curl to do the requests.
So something that I can open a resource over HTTP using GET request, edit the
RDF contents and save my changes using PUT request.
Basically I want to be able to use the SPARQL 1.1 Graph Store HTTP Protocol or
LDP to access the resources.

Probably easiest would be to use Turtle, so the relevant Accept and Content-Type
headers need to be sent with the request.
Must support HTTP basic authentication too.

Syntax highlighting/validation would be a bonus although simply being able to
edit a text is sufficient.

Cheers,
John