Actress and writer/producer Tina Fey ripped on Paris Hilton in an interview with Howard Stern in November, 2006. She dished on how immature Paris was when she appeared on Saturday Night Live, annoying cast and crew and coming up with idiotic suggestions for skits. Here's the relevant part of the interview in case you'd like a refresher. She called Paris a piece of shit and said she's dumb and self important:
HS: What is Paris Hilton like?
TF: She's a piece of sh-t. The people at SNL were like maybe she'll be fun, maybe she won't take herself so seriously. She takes herself so seriously! She's unbelievably dumb and so proud of how dumb she is. She looks like a tranny up close.
HS: Was she bad on SNL, was she hard to deal with?
TF: She was awful. People never come in and say "I'm not doing that." So, this guy Jim Downey wrote a really really funny sketch, it was supposed to be Lorne Michaels just finding out that she had a sex tape and telling her she couldn't host the show because SNL has standards So she was like "I'm not doing it!" and refused to come out of her dressing room. Also, you would walk down the hall and find what just looked like nasty wads of Barbie hair on the stairs Her hair is like a Fraggle.
HS: Did she give you ideas for sketches?
TF: Yeah, she wanted to make fun of all the girls she hates. She was like "I want to play Jessica Simpson, I hate her." She would come in the room and say "you should do a show about Jessica Simpson because she's fat."
HS: What was the bet you guys had going about her?
TF: The cast had a bet if she would ask anyone on the cast anything about themselves, you know like how are you? where are you from? anything. I think Seth Meyers won because at one point, she asked him if Maya Rudolf was Italian.
[From US Weekly]
Star Magazine has quotes from Tina Fey's interview in Gotham Magazine's yearbook issue, and the Golden Globe winner reveals that it was her gynecologist that made her have second thoughts about her public diss of the heirhead. Can you just picture her laying there in the stirrups with a contemplative look on her face? Anyone who criticized me at that point would get special consideration due to the circumstances:
When Tina went on Howard Stern and dissed Paris Hilton she got flack from her gynecologist! "She was like 'That was very hostile. Are you alright?' And I was like, 'You know what? You're right What business is it of mine?"
[Excerpt from Gotham Magazine article found in Star Magazine, print edition, January 28, 2008.]
Tina also spoke out in her characteristically blunt way about the unreal standards for beauty in Hollywood. She said "I think TV has conditioned our brains to see fake teeth and fake tans and fake lips, so when you see a normal person, you're like 'Oh, that's disappointing' I'm probably always disappointing, with my crooked teeth and thin lips."
Tina looks hot to me and that's great that she never fell prey to the plastic surgery obsession that plagues so many of her colleagues. She's lovely and it would never occur to me that there's anything wrong with her mouth, especially considering the awesome observations that come out of it. Anyone that says Paris Hilton has Fraggle hair deserves our utmost respect.
Ms. Fey is supporting her fellow writers in the WGA and has been seen picketing. There are new informal talks announced between the The Writers Guild of America and the Alliance of Motion Picture and Television Producers, and the hope is that they will become full negotiations and that the strike will be resolved soon. There is hope that the strike may end in time for the Oscars.
Tina Fey sis shown at the Emmys on 9/16/07, where she won for her show 30 Rock. Thanks to PRPhotos. 
