The movie Tron (by Steven Lisberger, made during 1979-82) was quite a distance ahead of its time — especially in its use of a plot element, computer consciousness, that has since become almost ubiquitous. Tron was also a trendsetter in special effects: it combined live action and computer-generated imagery (CGI) with excellent results in many scenes.

But CGI was extremely expensive back then, and so the producers couldn't afford to leave out much of what they had invested time and money in. Hence, I suspect, a short sequence spliced in for no apparent reason: one character says, "Watch out for the Gridbugs!" and there follows a few seconds of cute but absolutely irrelevant animation.

Gridbugs come to mind whenever I see a distracting flaw in a film or other costly enterprise (e.g., a programming project) — whenever something arbitrary is thrown in because it's a sunk cost and no one wants to admit that doing it was a mistake. "Watch out for the Gridbugs!"

TopicEconomics - TopicArt - TopicEntertainment - 2001-11-07

Wish I could email this directly to my boss! The term 'sunk cost' is what education is all about. "Watch out for the Gridbugs!" – Judy Decker

I disagree with your assesment that the Grid Bugs were a bad idea. I think they were left in because they were probbalya really cool idea they just couldn't expand on. In a movie universe I don't some ranodm things like that thrown in just to give the viewer a taste of otehrs things, or types of things that live in that world.
Even though only on for an instant I likved the grid bugs and do wish they could have had what you know would have been the fulls cene of hordes fo grid bugs chasing them.

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