MSNStockQuote is a very useful function to get stock quotes live into your worksheet.

You can pass a parameter to get various values like dividend yield, 52W high, 52W low etc.

Although it says it is for excel 2002, it does work with excel 2003 & 2007. I do remember some initial glitches when I upgraded from excel 2000 to 2003, but after some teething issues, it worked.

One Gotcha:
I could not get this to be updated by my macros. The 'update' had to be done manually. (So, I switched to downloading a CSV from yahoo finance)