Experiences made with free and open source software in scientific research. This is to share experience made with open source software (OSS) in the public research with the community. After introducing some background and pinning down the author’s research area, the pros and cons for publishing OSS are discussed from the research perspective. Then, several case studies are given to show how OSS and research work may influence each other. The emphasis is on checking the original motivation and the spirit of OSS back with the reality. Finally, future potentials of research OSS are outlined. The talk concludes with summarizing the experiences wrapping up the presented results. Introduction The IHP is a publicly funded research institute in the fields of silicon–based systems, highest–frequency integrated circuits, and technologies for wireless and broadband communication... [explicated in full paper] Among two other fields of applications, the Wireless Systems department conducts research and system–level development in the area of wireless sensor networks (WSN) and middleware platforms. For many years, the author contributed to the evolution of mobile, context–aware software, recently with a focus on health care applications. Technically, the author is dedicated to software development for tiny, resource–constrained sensory devices.