I think I've missed a week or two and I also don't remember what day I wanted to set aside for this. Sorry, but this might happen time and time again because I suffer from ADD ;p
I'm not sure what Id like to call this..but I love when there are female duet dancing songs of either sisters or best friends.
50s: Film: Azaad Song- 'Aplam Chaplam..'
forget the remix, listen to the original! These girls dance so well and they are also sisters in real life.
60s: Film: Parasmani Song: Hasta hua noorani chehra
I love this song, made popular from the pillow game scene in 'Hum Aapke hain koun'
7os: Film: The Burning Train Song: Meri nazar hai tujhpe
This is actually from 1980 but I really love this song and I think it still represents the 70's era
80s: Film- Joshilay Song-'dhak dhak jiya kare'
90s: Film: Kshatriya Song: Dil na kisi ka jaye
2000s: Film: Har dil jo pyar karega Song: Piya Piya o Piya
I have to add in a honorable mention to Karisma and Madhuri's Dance of Envy From Dil to Pagal Hai because it is too awesome.