"IFFY" is an alarm clock with a unique additional feature. It allows you to set alarms which are conditional upon receiving a Twitter or SMS message.
This app was developed in an area of Canada that has heavy snowfall and frequent cancellations due to snow. Twitter and SMS messages are sent in the very early morning to cancel bus routes and even cancel school. The IFFY alarm clock can monitor for messages and on those days tell the alarm not to ring! A student using the IFFY alarm clock will be able to sleep undisturbed.
Snow truck drivers are able to set alarms that wake them up for their early morning shifts only when they receive a message that it is a snow day!
Of course there are many other situations where it might be useful to enable or disable an alarm based upon external messages.
Do you work at a job that gets cancelled on rainy days? Let your boss send out a message on those days and your IFFY alarm clock will let you sleep in.
Are you on call? Set an alarm that only turns on when you have been messaged to come in to work.
Even if you don't need conditions, IFFY is a great alarm clock for normal use.