Being an extra on The Big Bang Theory sounds like a fun and enjoyable experience. According to a Reddit post, extras had to follow a specific rule regarding their wardrobe color. They were not allowed to wear colors that conflicted with what the main cast was wearing, so they had to choose more unique colors. The extra also shared that the food on set was great, and they had the opportunity to meet actor Kunal Nayyar, who was very friendly and approachable. Overall, being an extra on The Big Bang Theory was a fascinating and memorable experience.