Molecular biologists have been observing interactions between messenger RNA (mRNA) molecules and other non-coding RNA molecules for quite some time. Here I revisit some of the classical hybridizations between the 16S ribosomal RNA (rRNA) and mRNA during initiation, as well as investigate the interactions between small interfering RNA (siRNA) molecules and mRNA. In reviewing rRNA-mRNA interactions, I observed that the majority of both bacterial and eukaryote genes can bind at the start codon. This novel result lead to a method for improving genome annotation as well as a new theory of translation initiation. The examination of siRNA-mRNA interactions lead to new criteria for predicting an siRNA's efficacy.