Moving away from offering just physical artifacts to becoming providers of functional products, or Product-Service Systems (PSS), implies inevitable changes in the way engineering knowledge is identified and shared in a cross company environment. Capturing downstream knowledge assets and making them available to cross-functional teams becomes crucial to approach ill-defined problems in PSS design. The purpose of this paper is to investigate how Web 2.0-based knowledge sharing technologies may be used to support the design of functional products. The article, drawing on data from several industrial development projects in various segments, introduces the concept of “lightweight technologies” as a means to lower the threshold related to the sharing of downstream engineering knowledge assets. The paper points out potential benefits and challenges related to the adoption of a lightweight approach and provides examples of how tools like wikis, blogs or social bookmarking may be used to support functional product engineers.