The Sumatra Andaman quake that generated the tsunami also made the Earth ring like a gong. Some of the tones last longer than others - the most fundamental frequency is still ringing, expanding and contracting the Earth radially, and should be detectable well into April.
We have to use very special techniques to see this, since the period for this harmonic is quite long - about 20 minutes. So it's really more like a very low groan than a ringing gong...
IRIS has a lot of info on this. Here's an audio file (.au format) of what it sounds like, speeded up about 200,000 times.
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