Wow, I just ran across this today, Google Finance.
It’s very in depth (compared to Yahoo!’s, and has no ads). I’ve been interested in stock lately, and I want to get some of Apple’s soon… 
Well, I need to clean my stuff up since I’m moving, so that’s all for now.
EDIT: I guess I didn’t know what I was talking about, here’s an article that kinda talks about Google’s new Finance service: http://www.redherring.com/Article.aspx?a=16206
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