Windows only: If you're a fan of Microsoft Security Essentials antivirus (and many of you are) but not a fan of the pesky Windows Update, MSE Update Utility will keep your virus definitions up to date without Windows' unwanted help.
A lot of situations might call for turning off Windows Update — larger networks like a company or university sometimes do their own updates, but more likely you just plain don't like its frequent reminders (which we understand). In the past, if you were in one of these situations, you had to update MSE's virus definitions manually. Thankfully, Nakodari at AddictiveTips created a small update utility for MSE that allows you to automatically keep your virus protection up to date, even when the rest of your system isn't.
From the app's main window, you can choose the update interval (daily, weekly, monthly or at startup), and you can choose whether the program runs on startup. It will automatically update your virus definitions in the background and let you know when it's done.
MSE Update Utility is a free download, Windows only.
AU editor rant: If you can't be bothered keeping your system patched, then there's scarcely any point in running a security package IMHO. Exploiting known vulnerabilities is the most common way for malware to get onto a PC. Yes, Windows Update is painful, but being part of a botnet is more painful. End rant.)