New English Word Proposals (Neologisms), Part 1:

This is the first in a series of words I want to invent and, both aggressively and subliminally, foist onto the English-speaking world.

"UNTERESTING" : definition = a light proclamation of disinterest proferred in an ironically encouraging manner.
Example: When someone is rattling on about, say, colour therapy or what courses they wished they'd taken at University instead of taking hundreds of drugs and dropping out of environmental studies, you can maintain attentive eye contact and deliver the faux-bolstering, "Unteresting... do go on". Keep doing it until they notice or don't. It's fun - and fun is anything but unteresting.