Squeezebox - S6-E20
Continuity mistake: Kelso gets really close to Eric when he's trying to burn him about the other girl. The shot changes, and Kelso is further away.

Starring: Mila Kunis, Ashton Kutcher, Topher Grace, Danny Masterson, Laura Prepon, Wilmer Valderrama
Squeezebox - S6-E20
Continuity mistake: Kelso gets really close to Eric when he's trying to burn him about the other girl. The shot changes, and Kelso is further away.
Visible crew/equipment: In the scene in Bargain Bob's where Donna is talking to Bob, the end of the set and lights can be seen in the reflection of metal cookware that Bob is tying balloons to. (00:07:50)
Red Foreman: Steven, when are you moving out?
Hyde: Soon.
Red Foreman: How's your girlfriend?
Hyde: Shallow as hell.
Red Foreman: Job?
Hyde: Dead-end.
Red Foreman: Future?
Hyde: Bleak.
Red Foreman: Kitty, feed the boy.
[Kitty takes Eric's plate and gives it to Hyde].
Trivia: The show was originally titled "Teenage Wasteland" or "The Kids Are Alright" but those were songs by The Who and, legally, Fox couldn't get permission to use them. They renamed the show "Feelin' Alright" to show the focus groups. However, nobody really liked the name. After the focus groups airing, the audience were heard saying they really liked that show about the 70's or that 70's show - and the name stuck.
Answer: It's Ashton Kutcher's dog.