There is no escape...believe it or not. Mathematics is everywhere.
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Here is what is on my list:
Maths 300 software (www.curriculum.edu.au/maths300), TI-SmartView, GeoGebra, Cabri Geometry, Jing (instant podcasts), Scratch, Logger Pro, National Library of Virtual Manipulatives (nlvm.usu.edu), Rekenweb (www.fi.uu.nl/rekenweb/en), Google Docs (especially shared spreadsheets, surveys, etc), and the plethora of free or cheap software for iPod Touch/iPhone.
I have a few hundred other useful items, but I keep coming back to these ones.
Regards, Matt Skoss.