Share prize money from conference presentation award with co-authors? I am a PhD student and I recently won a young scientist award and prize money (~500 USD) at a conference for the "best presentation". I did the majority of the work for the presentation, and I was the only one present at the conference.
However, my co-authors (8 people) all wrote their share for the conference proceedings (that's what makes them co-authors). The co-authors are in various stages of their career, from professors to fellow PhD students.


Should I share my prize money with the co-authors? If yes, with all of them in equal amounts? Or only with those who would be eligible for a young scientist award themselves?
Would it change the situation if I won the award for something else, say "best paper"?
I think that it is important to recognize that the biggest value of the award is its contribution to your C.V. and future career, not the prize money.  As such, I think you should approach the question of the money as generously as possible: after all, you gave a good talk, but many of the aspects of that good talk depended critically on the contributions of your co-authors.

What, then, is a fair way of allocating the money?  Pretty much any numerical formula that you follow will both a) leave some people feeling that their allocation is too big or too small and also b) only be a few dollars anyway, given the number of people involved.  

I would therefore recommend defusing the question entirely and turning the prize money into an investment into future goodwill and papers: suggest that it be spent on going out for a fancy dinner together (or similar such outing) to celebrate the success of the collaboration!