Well, the other thing many of the proprietary systems give you is a machine readable version of the tax code. Depending on the type of business, this could easily justify the subscription costs.
Unfortunately, this data is fairly localised and there can be large penalties if the data is wrong. So it isn't clear that a community project could take over this role.
If the free accounting systems had a standard interface for this type of data, it could provide a business opportunity for companies who were willing to provide the data though.
Posted May 10, 2012 14:48 UTC (Thu) by dgm (subscriber, #49227)
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Even if the details (tax code) is strongly local (both in space and time), a general engine open for extension via plugins should be possible. The explanation about how C1 works by Cyberax seems a good starting point.