UPDATE: This is now out of beta and is available to all users.
We have pushed out a new feature this morning, and it's now available to all opt-in beta users to try out. For more information about opt-in our beta program, please check this wiki page. Do note that currently alternate front page is also in beta, but you can change to List view to get the current front page back.
New Feature: Search Alerts
Basically it allows you to create "Search Alerts" so that you get an email notification if new posts match your search criteria. For example interested in any Nexus 7 deals? Search Nexus 7 on OzBargain, and click on "Create Alert". You'll then get an email from us when a new deal or a new forum topic has been posted that contain words "nexus 7".
Some implementation details — we will re-run the queries once each hour on all the new posts, so you will get an email at most once each hour for all your alerts. There is also a maximum 10 alerts at the moment. You can manage your existing alerts from your Subscriptions -> Events page.