My friend Steve Dekorte suggested that I have a go at the old shareware game. He makes a comfortable living off a collection of Mac mini-apps that, he tells me, pull in about the same per year as he got working at a dot com. When I worked at dot coms I got paid above average so it sounds like a pumb to me.
Apparently Windows shareware developers make a lot more than Mac shareware developers, so I've cranked out a (hopefully) useful app called TcpSafe on Windows. It allows you to monitor where your computer is connecting and who is trying to connect to your computer. Good for catching spyware and trojans that "phone home" in the act, debuging sockets applications, troubleshooting network problems, monitoring the network for worms and hackers, etc.
I'm using Paypal for a payment system and I've integrated it into both my web site and the application. The licensing system is per machine. So if you want to use the registered version on multiple machines you've got to pay multiple times. As such, I've set the price really low ($9.99) and hopefully we'll make up for it with volume.
Steve had this great "I've Paid!" button idea which I've duplicated. So if you need to reinstall the software for some reason and it comes up in evaluation mode you can just hit the button and it downloads your license key automagically. Support costs are apparently the killer in shareware, so here's hoping everything runs smoothly!