We have discussed issuing a Greek text for the NT (the Greek text actually translated to produce the NET Bible) as well as a Greek-English diglot (English NET Bible text on one page, Greek on the other) for the NT at least. The latter is now available in our online store. An interlinear would be rather more complex to handle at the present level of word processors because it would involve keeping lines properly aligned when the text is repaginated. This is a future possibility, but we have no firm plans to produce one.