This phrase seems to be
Silicon Valley slang. Used generally, it refers to
believing religiously in the New Economy; more specifically, it's used to refer to believing your own
propaganda, or that of whoever you're with: You're
on the team, "
signed up", committed to the madness at hand, etc.
I'm guessing that it derives from the
LSD-spiked
Kool-Aid in
The Electric Kool-Aid Acid Test by
Tom Wolfe.
References:
Sense 1:
http://www.lvdi.net/~intercon/Archive/SUM0706.TXT
Sense 2:
http://www.salon.com/tech/feature/1999/10/13/vc_class/index2.html
http://www.wired.com/wired/archive/8.04/jwthompson_pr.html
I've also heard it used, only once, in the
Jim Jones/
Heaven's Gate sense of "
Kool-Aid": A
VC who has "drunk the
Kool-Aid" is one who has pumped enough money into your cult that he'll have no choice but to die with you when the time comes. The more I think about it, the more I doubt that this usage differs from the above, except in the sense that the speaker has thought it all through.