In this talk, inkjet-printed flexible antennas, RF electronics and sensors fabricated on paper and other polymer (e.g. LCP) substrates are introduced as a system-level solution for ultra-low-cost mass production of UHF Radio Frequency Identification (RFID) Tags and RFID-enabled Wireless Sensor Nodes (WSN's) in an approach that could be easily expanded to other microwave and wireless "cognition" applications. The talk will also touch up the state-of-the-art area of fully integrated wireless sensor modules on paper or LCP and demonstrate the 2D and the first ever 3D sensor integration in the form of module-on-paper, that could potentially set the foundation for the truly convergent wireless sensor ad-hoc networks of the future with enhanced cognitive intelligence and "rugged" packaging. Various examples encompassing temperature sensors, carbon-nanotube-enabled inkjet printed gas sensors and crack detection sensors will be covered in detail.