Recently I discovered that the Environment Agency published water levels on it’s website, however other than a two day graph it didn’t have an real historical data.
So I went about and created a script to scrape the data for me. This ensures that I have data past the 48 hours and allows me to see exactly what kind of changes have taken place say in the last week.
Now as I was already collecting the data, it seemed sensible to create a twitter account to publish key changes. So I set up @sincildrain. It has some pre-defined boundaries which if the levels go past it sends a new tweet.

Going down, latest recording on Fri 28th Dec 04:30 is 1.79m

— Sincil Drain (@SincilDrain) December 28, 2012

With the Twitter for Android app, you can then set notifications whenever an account tweets, like the old days when you used to get an SMS from each one. So now I near time information on the water levels of the drain just meters down the road.
However the great advantage of Twitter is it’s one-to-many broadcast method.
Previous bots I built would either email or MSN message an update, but to scale required building in subscriptions, anti-abuse and stop methods.
But Twitter does this already, my bot just needs to tweet and with public visibility anyone can follow the account to also get the latest updates, at present 44 people are checking to see if the water levels are too high.