I don't know how I missed it but I didn't realize until yesterday that there is such a thing as Google Alerts. Basically the service lets you watch the internet for interesting content and sends you email digests whenever it finds what you are looking for. You can even tell it to track only specific websites, which is really great. For example, I have been looking for something (rather rare) on two local advertising sites and I kept checking every few days to see if someone has advertised it. Then I discovered this service. I haven't received any alerts yet but I find the service very promising. Anybody using it? What other cool but somewhat obscure internet tricks do you use?

Actually I am not surprised. It's not your everyday product I am looking for. I expect it will be a while before it shows up.