Futurama, is full of stuff like that, it's what makes it a great show! All sorts of little things to look for and notice if you
know what to look for. One of the best things I've ever seen with Futurama is the special they did "Bite My shiny Metal X" on the DVD for Bender's Big Score. It gives you an look at some of the math these guys put into Futrama. It really makes you want... need to go back and watch again and again to look at the chalkboard behind the Professer and say... Wha?!
a^2 +b^2 > c^2
The cultural references numerious and often obscure. I'm sure most of you guys know that Welshie was put into the "Where No Fan Has Gone Before" episode to be the "red shirt" - the nonimportant character to be killed.(multiple times) But how about how aweful the Mets play in the 31st century... oh wait I guess that's a given from the 21st century... my bad.