Write your own update center module
An Update Center module can be an addon module or an archive module. For an archive type module, the addons.* interfaces need not be implemented. Let's take a closer look at the addon module.
There were several recent additions to Update Center including Apache Roller. If you ever wanted to know how we did that, here is the code for roller.
Hope this will get you excited enough and started on your own module! Send me your comments.