[consulting] DrupalCon Boston, March 3rd - 6th, Job fair March 3rd: 3PM-5PM, Sprint March 7th

[Karoly Negyesi]

OK, now I read the relevant sites and
http://hungary.usembassy.gov/visa_requirements.html states

Evidence concerning the purpose of travel (e.g. in the case of a
business trip or an official visit, a letter from the employer or from
the inviting party in which they state the purpose and the duration of
the visit).
If the person you are visiting has been in the United States less than
10 years, please provide evidence of their status (green card, visa,
U.S. passport, etc.).

So yes, an invitation letter might be needed -- but then again the
Drupal community is big and you might get a mail from someone.