Tsunami Relief–what is a good charity to help the tsunami victims?
Your national Red Cross / Red Crescent organisation is probably able to collect and transfer funds. They may have an existing fund-raising structure for the tsunami from earlier this year.
The Indonesian RC organisation - Palang Merah Indonesia - webpageis in Bahasa but with a translation function into English as well and accepting donations.
I expect at this stage focus is mainly on disaster relief and temporary housing, feeding and health of the dislocated. If you have a particular interest in supporting recovery programs, like school rebuilding for example you might need to wait until those charities gear up.