veins and arteries
"Veins and arteries are like one-way streets and when a blood clot forms it can make a roadblock. In a sense, the blood behind the clot gets caught in a traffic jam."
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.