Ping Transmit. This past summer I was maintaining a test environment where the most reliable thing was the internet connection. I started with a ping script that stored pings locally, in a text file. I wanted a web page, but I also wanted isolation between the web page and the customer environment. Enter Iron I/O.
The ping routine itself is in perl. I reworked it to output JSON, then wrote some python to take each new ping and push it to a message queue. An Iron I/O "worker," also in python, unspools the queue into an ephemeral database (Iron Cache). A third python program reads the data on request from a web page, and displays it via YUI.
That project is over, but the data is still there (hooray for IronCache uptimes). For this project, I'm starting the ping daemon again in my own lab, an environment I should be monitoring anyway.