Google Alerts offer a search-based notification. This means... you can specify search terms and it will send the related activity to your inbox, "as-it-happens"!

Ego-Trip
I created a few search queries for my 'blogspot' blogs and my alias 'aksn1p3r' so that I know when anyone is typing about me or if they link to my blogs. Afrigator usually talks alot about MyDL users as every post on MyDL is indexed by them. Get that personalized tracking system to know about your presence and activity online.

Keyword Optimization (for SEO-lovers)
If you have a blog and you know your site's most organic keywords... create an Alert on those keywords. You can then receive notifications that portray how the competition use those exact keywords. Be it to get a higher standing at Google (PageRank) or just for pure entertainment, it helps to know your site's top keywords.


Experiment!
Play with Google Alerts and also remember this, you can create spam. A test search query at Google will be enough to know your relevant keywords. Variate keywords and their derivative words to create a variety of relevance to your Alert. This way you can stay up-to-date with your favorite developments and have an even more sufficient web-experience.

technorati tags: Google, Alerts, Keywords