"To continue my family metaphor, immunotherapy is like hiring a team of psychologist to follow your family members around and constantly correct them from acting badly. Chemotherapy is like hiring a black ops team to kill anyone with your last name." The link is worth reading in full.
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.