Has anyone seen/made/heard rumor of an extension to add a data source for
simply making regular local php variables like $myvar available in the bindings
tab.

If not, I was looking at making one based on the URL variable files for the
bindings tab. I think the only thing I can't readily figure out how to modify
to a local variable extension is in the URL_DataRef.edml file at it is these
two nodes:

<quickSearch><![CDATA[_GET]]></quickSearch> (would
<quickSearch><![CDATA[]]></quickSearch> work?)

and

<searchPattern
paramNames="bindingName"><![CDATA[/\$(?:HTTP)?_GET(?:_VARS)?\['([^\r\n]*)'\]/i]]
></searchPattern>
Any help would be appreciated. I've always been surprised that this isn't
already built in, so maybe it is out there somewhere and I can stop typing the
same local variable names repeatedly