The Canadian Red Cross: Canadians can donate online or by calling 1-800-418-1111. Text "REDCROSS" to 30333 to have a $5 donation added to your wireless bill. To confirm your donation answer "YES" when prompted in the Red Cross' follow up text.
The American Red Cross: Donate online or via text message. Text "REDCROSS" to 90999 to make an automatic $10 donation.
Doctors Without Borders/Médecins Sans Frontières: According to the organization's site they already have two three-people teams trying to reach the worst hit areas in Japan. Support their efforts with an online donation or by phone at 1-888-392-0392.
Shelterbox: This organization delivers aid boxes to the displaced and homeless and accepts online donations.
International Medical Corps: According to the organization's website "every dollar in private contributions generates more than $30 in additional grants from institutional donors and donated supplies." You can contribute online.
Convoy of Hope: A non-profit that specializes in disaster relief efforts and accepts online donations or donations by text (text "TSUNAMI" to 50555).
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I'd love to hear any other ideas you have.
I hope you all have a wonderful and safe weekend! xo