Viewing any kind of sexually stimulating material (not necessarily illegal or even explicit) on the internet. In common use in northern England, and possibly elsewhere, this expression originates from pop musician Pete Townshend's explanation of why he gave his credit card details to a website containing visual depictions of children being sexually abused - that he wished to view the material for research purposes. Although the implication of the term is that Townshend was lying he was, in fact, cleared of all charges.
Sorry I didn't answer the phone, I was doing some Pete Townshend-style research.
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