node.js cross domain and chrme extension
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I plan to build an service for price following. etc. user come to my web service type email address and get a browser extension bookmarklet. With that bookmarketlt when shopping online he mark the price from some product... so after that every day we see if there any changes with price (up,down, when is the best time to buy)

-user click,save xpath to database,check every day for chaneges,send email if there any changes


So my questuon is:

1. Is this a good idea?

2. Can I use node.js to automaticly show me the price changes or I need to use some other tehnologies?


really sorry for my ebglish is not very well

THANKS