Kaspersky Software Updater is a free tool which regularly checks for updates to critical software, alerts you when any are discovered, then downloads and installs them with a click.
It's not entirely clear which software is supported, but from our tests it seems to cover the main internet-facing applications: browsers, Java, Flash, Adobe Air and so on.
In our tests this worked without issue. You're able to schedule scans to run daily, on weekdays, at weekends. monthly and more; if an update is discovered, a notification is displayed; you can decide which, if any to install; click the "Update" button and the upgrade is downloaded and silently installed for you.
What you don't seem able to do is to tell the program to ignore a particular application. If you'd rather manage Java with its own updater, say, you're out of luck: Kaspersky Software Updater will look for and warn you of any new patches, whenever they're detected.
Kaspersky Software Updater is extremely basic, and doesn't appear to support very many applications. But it worked well for us, and we suspect Kaspersky will provide the funding and maintenance work to keep it reliable in future.