„For one day only, you can get an ad-free version of Opera. Simply e-mail registerme@opera.com to obtain a registration code. This offer is valid from 12 a.m. Tuesday, August 30 to 12 a.m. Wednesday, August 31 2005 (PDT).“
Faster is to try this page: http://my.opera.com/community/party/reg.dml but it seems quite busy now:)