You may already be aware there is a pretty serious vulnerability with Java that has just been patched (see Security Alert for CVE-2013-0422 Released ) on pretty much all versions of the program. For some people however this may get them questioning if they need Java installed at all on their computers. Personally I have uninstalled Java off my friends and family computers for the past few years without anyone every complaining. Certainly other Microsoft MVP;s are also finding that having Java disabled in the browser seems to have little of no affect (see https://twitter.com/troyhunt/status/290589939782000641 ) as most web sites no longer user Java applets. However as an avid gamer IT Professional I am fully that some programs require Java to be installed to allow the full desktop apps to work (like Minecraft). So you may be please to know there is a way to Disable Java in Internet Explorer thus greatly reducing the risk of having Java installed…
While Java is not normally configured via a registry thanks to @rickd4real (Via) @stealthpuppy I have been able to extract the Group Policy Preference Registry file that you can quick import into your GPO to disable Java in IE for Users of Computers.
Disclaimer: Use at your own risk. I am trusting the registry keys provided are sufficient to disable Java.
Update: Additional info at Microsoft KB : http://support.microsoft.com/kb/2751647