Topic: statistics of anything

a very very raw idea ...

A website or a product that has the ability to monitor other web pages and their content, specifically numbers such as prices, scores etc. A user can create their own public or private reports and specify things that are to be monitored. The program collects the data once a day (or so) and uses among other things Google charts to present it.

Does such a thing already exist? What do you think of it?

Indeed, it does exists, and is used by to monitor downstream sellers and the like (make sure nobody messes up your 'high price' brand image...).

Actually, the company I work for has such a product (parts of it were even written by me .
Basically you create a template for each shop, telling it where prices are, etc., and specify what products to monitor,
and you get detailed history and warning if anything interesting happens.
Expensive, though.

So long,

->Tyberius Prime

are there any free/ open source versions?