OPW; Where does the 500$ for each GSoC goes?

[Sébastien Wilmet <swilmet gnome org>]

Hello,

I know that money and OPW are sensitive topics, but I would like to
better understand, and some transparency shouldn't hurt.

For each GSoC student, the mentoring organization receives 500$. How is
this money used?

- Is the money used for travel sponsorship to GUADEC? What about
  students that don't go to GUADEC?

- Can the mentor receive this money? Or at least choose how the 500$ is
  used?

- Can the money be stored so that several years later it can be used to
  pay a developer for working on the same module(s) of the GSoCs? For
  example the GStreamer project donated 2500€ to the Pitivi fundraising
  campaign, and this money comes partly from several GSoCs:
http://blogs.gnome.org/uraeus/2014/03/03/pitivi-fundraiser-pass-the-10-000-usd-dollar-mark/

- Is the money used for something else, like OPW? I've read an old blog
  post that suggested that the 500$ could be used to finance a few OPWs,
  that's why I ask.
  
  Or is OPW financed entirely by the sponsoring organizations and
  companies listed in https://gnome.org/opw/ ?

  But it seems logical to me that, for example, the Linux Foundation
  pays only for the OPWs related to Linux. So which companies or
  organizations finance the GNOME OPWs? Philip Van Hoof suggested that
  this money could be (better) spent on developer tools, which would
  indirectly achieve outreach too (women included of course).

I think this kind of discussion should be entirely allowed, and should
be discussed in the open.

Thanks in advance for your answers,
Sébastien