Most modern routers allow you to backup/export its full configuration, and restore them from this file when you need. The router configuration file (like TP-LINK's config.bin, it varies according to the brand and model of router) usually contains info including your ISP username/password, router's login password, wireless network password, etc. RouterPassView enables us to get a sweeping view of all this.

WirelessKeyView is a tiny app written by the famous freeware developer Nir Sofer, designed for recovering the lost/forgotten wireless network keys which you have logged on successfully before. But please note that this tool is not used for unused wireless network.