IBM Watson Research Centre undertake research in collaboration and collaborative tools (mainly under the Lotus brand). IBM have been working on a project, affectionately entitled ‘Dogear‘ (as in the somewhat destructive practice of folding over pages in books ), which is basically [pauses for a moment to check whether IBM lawyers are around, mindful of the fact that a lot of devlopment effort has been expended on this] del.icio.us for the Enterprise. Obviously this is a masterstroke of understatement in terms of the effort that has gone in to the project, so bear with me whilst I run through what they’ve done in a more positive analysis 
For those with an ACM login, you can read an article in Queue, and Watson Research Centre Research Papers are here for those who are academically inclined.
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Paul lives, rides and works in Cardiff, South Wales. His work seems to largely entail fixing things and keeping wheels on. Officially, he is actively engaged and interested in Enterprise Architecture these days, but has a secret past that involved standing around on glaciers collecting meltwater samples, and walking through endless fields of wheat taking radiance measurements. 