If sushi isn’t your cup of tea, and you still want fish on a Monday, you can always cook it yourself. Many retail fish markets get in fresh shipments every day that you can select from. When shopping for fish, it’s important to follow your nose. The older the fish, the more pungent it becomes. A fresh fillet shouldn’t smell particularly fishy; instead, you ought to detect a cucumber-like scent [source: Brown]. Also inspect the condition of the flesh. Go for fillets that appear brighter and slime free [source: Food and Drug Administration].