F-Secure Router Checker
A free, web-based tool that checks your router’s settings and detects if it may have been hijacked by criminals. If your router is compromised, every single device on your network is at risk of being hacked.
ShieldsUP!!
Scans UPnP or Universal Plug and Play, that is enabled by default in most consumer routers.
It also has a Custom Port Probe tool for scanning any port of your choosing plus a useful port information tool.