HP, Digital, Tandem archives
5-minute rule paper
As academia becomes more stagnated it makes sense for companies to open up and spread knowledge to drive their particular ecosystem forward.
Not to mention it's probably an excellent recruiting tool.
The research talks are also worth checking out: http://research.microsoft.com/apps/catalog/default.aspx?t=vi...
The latest talks range from "Culture differences between US and China" to "Distributed Optimization via Alternating Direction Method of Multipliers".
Not sure if I saw an old page, or if something has changed in the past couple of weeks, or what, but at least for now, it appears that a significant body of IBM research material is still freely available.
And to make it even more confusing, I now see that some links from http://researchweb.watson.ibm.com/journal/ redirect to the IEEE site, but the actual article is still freely downloadable. Not sure how universal that is, as the article I was trying to access a couple of weeks ago, was very much not available for free (at the time). Weird. shrug
Tools like CiteSeerX can help you find archived copies of papers around the Internet, which may mean that you will not have to contend with paywalls at all to read the papers you want. For example, Tomasulo's famous paper about out-of-order execution originally published in the IBM J. Research has an entry here http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.129.... and you can note that it is available on several academics' personal sites, presumably uploaded originally for pedagogical purposes. As well, CiteSeerX keeps a cache of quite a few citations locally.
This creates an incentive for companies to find ways to report their work as R&D. (Not implying that Twitter is defrauding or that their work isn't R&D, just stating why it might be useful for a company to "invest in" R&D, especially if that is work they wanted done anyway.)
Things such as their discovery tab, targeted tweets, trending, search and user search most likely involve (Or involved) reasonable investigation.
I was in research before (IT security) and I often found interesting results from companies such as IBM, Intel, Microsoft and Google.
What I think is kind of strange here, is that there's not a section on security/privacy in the page... well, but perhaps I'm biased ;)
In my view, I love Microsoft Research.
Dealing with how families interact on Facebook looks to be particularly interesting.