How much can everyone hold?
I've found with beer I can sit there and pound an 18-rack with no problems. Hard alcohol, depending on what exactly, is harder to regulate.
I've only puked twice. On my 21st birthday I went out with my roomate and a bunch of friends. Had over 12 shots, 7 beers and 3 mixed drinks, plus a shot of everclear when I got home. It was a bad morning.

h:
Only other time is when I drank too much being dehydrated (sitting outside all day then drinking)