The folks at 28msec, the creators of the SECXBRL.info public company financial information repository have told me that now they are making 100% of the information in their repository available for FREE for noncommercial use. (In the past you could only access information for the DOW 30.)
As I understand it, EVERYTHING from the SEC EDGAR system is now available.
To understand the sorts of things you can do just go fiddle around with the repository. Information is available in human-readable HTML and machine-readable XML, JSON, and CSV.
Here is an updated set of queries against their repository. That set focuses on cross entity comparisons. The queries pull sets of companies: DOW 30, Fortune 100, S&P 500, and Russell 1000. Look at the parameters of the examples I am providing (it is in the form of an RSS feed). Edit my URLs by changing the parameters to create the queries you want.
I will make some additional queries available over time.