I put Adsense on my website in 2004 on a Thursday. Logged in Saturday and discovered that I'd earned $25! I immediately click one of my own ads, then logged back in to check my earnings per click. Later that week I got a warning email from Google. Told my wife.

She made me take all of my Adsense ads down immediately for the rest of the month and the first couple weeks of the next until we received our first Adsense check.

Then, and only then, did she let me put the ads back up. That first check bought us a freezer. The next paid our rent.

Those were fun times: $50 CPM was not usual 2004-2005.