Many high performance computers (HPC) and cloud computing applications rely on distributing tasks among large numbers of virtual and real servers. This implies that advancements in performance of data centers and HPCs is increasingly dependent on connectivity. In order to insure high degree of connectivity at increasing bit rates and distances the demand for large bandwidth-distance product connections is increasing. These can almost exclusively be provided using optical interconnects. Traditionally optical-interconnect come in the form of pluggable transceivers. However the increases in number of connections and bit-rate poses a limit to further scaling (the front-plate bottleneck). A shift towards mid-board optics is in the making but requires solutions which are compact, power efficient and low cost for manufacturing. In this talk we will present our most recent demonstrations of high density optical interconnect solutions as well as high density switches. First some details about the design aspects and advantages of compact electronic switches employing mid-board optical engines will be discussed. Then, for addressing the challenge of low cost optical interconnects, we will give details on our recent work targeting high channel count VCSELs based sub-modules. Results based on 2.5D and 3D assembly on high resistivity silicon will be discussed as well as the use of direct die attach to flexible PCBs for making high density interconnects.