If oxygen is money, then hemoglobin is a wallet with 4 dollars. The dollars can be spent anywhere in the body. Myoglobin is a wallet with 1 dollar and it, usually, is only spent in the muscle in which it is stored.
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.