http://wikimania2012.wikimedia.org/wiki/Scholarships
Full travel scholarships, funded by the Wikimedia Foundation and chapters (France, UK, Israel, Austria), will cover transportation, hostel accommodations, and conference registration. Partial scholarships are also offered by WMF (and Wikimedia Hungary).
Wikimania 2012 will take place July 12-15 at the George Washington University in Washington, DC. Wikimania hackathon is July 10-11. The call for participation is also open now (deadline: March 18), and registration is open.
Cheers,
Katie