I read the Techdirt blog every day, generally via the RSS feed. Their usual themes are business models, law, and economics, with a US bias. One of today's posts is one of their best ever (IMHO), giving decent definitions of the above concepts: Patents, Copyrights and Trademarks. Oh my, indeed! It's nice to see these terms laid out simply and straightforwardly.
Patents: grant a monopoly to an inventor for 25 years.
Copyright: protects your creations from unauthorised copying, in order to incentivise future creative effort.
Trademarks: protect the public from confusing Bob's Cola with Coca Cola.
One of the most interesting points on the post though, is the 7th comment, where "Jerry in Detroit" points out that property is subject to property taxes, so why isn't so-called 'intellectual property" subject to property taxes? Default on your tax payments, and have your patents/copyrights/trademarks put into the public domain.
I wonder why we've never heard of such a concept from the US government? Perhaps Rep. Howard Berman (the "Representative from Disney") would like to bring such a bill to Congress?