Twitter is a service that is being updated thousands of times every second, so monitoring twitter for mention of your product of service is really important, we had told you about one such service earlier called Tweetbeep, which helped you monitor twitter for mention of your product or blog posts, even if the URL was shortened using a URL shortening service.
If you want such alerts on your desktop, Yahoo has released a Adobe Air based application called slider which allows users to watch, search and monitor the Twitter public timeline in real-time.
Sideline is an Adobe Air desktop application built with the Yahoo! User Interface Library (YUI). It allows users to create and group custom queries by topics of interest.
Sideline also shows you the current trends on twitter, based on the most talked about keywords or hashtags.