Via Ken Lee @ Macresearch: if you are an avid user of
and happy owner of the iPhone, there is a nice little iPhone program called LaTeX Help to look up often used mathematical symbols, the commands for including figures, etc. I know, it might be easier to look these up on the internet, but I like the idea;-)
Two other useful programs: a periodic table, The Chemical Touch: Lite Edition) and PhD Comics (very useful – and also available directly on the web ;-) Enjoy.