Throughout the episodes, Greg's eyes change from buttons to actual eyes. The first episodes were filmed with button-eyes but because the episodes are shown out-of-order, the types of eyes alternate.
The group 'Hyperjinx Tricycle', featuring Daniel Johnston, were approached to write the theme tune. However, their song "Greg the Bunny" was rejected. It now features on their self-titled debut album.
Greg the Bunny first appeared on a New York City public access show called "Junktape". He was then the star of interstitial short films and features on The Independent Film Channel for two years, under the show title "The Greg The Bunny Show".