Knowledge-at-work: Boundary objects and KM discusses the use of shared artefacts by different communities of practice, based on S.L. Star's "The Structure of Ill-Structured Solutions: Boundary Objects and Heterogeneous Distributed Problem Solving" (reference here).

"Reports are a classic example of traces as boundary objects that the professionals and other members share. Faxed documents and email massages are also the boundary object among distributed members."

"Information spaces, where particpants gather to exchange information, co-ordinate activites and create knowledge are another example of BOs"