lol i did this when i was at uni. We didn't have enough shot glasses so we used aerosol lids, which are quite a lot over a shot size.
I blame the Lynx flavour for making me puke, definably not my inability to drink so much Stella as i am a real man.
There was about 20 of us and i dont think anyone actually finished, and the bath was full of puke at the end. Funny night tho.
Only tip id advise, dont do it