I have a particular feature which has been orphaned and I no longer have access to re-install it. However it is locked in to three lists that I have in my site collection. I can find it in one of the lists because the list errors and notes the feature in the ULS logs. The other two lists i cannot find, I was hoping there was a way to search the site collection using powershell to see where this particular feature was being used...and i'm not just talking about which web is using it...i need to know what list/library in that web. If it is easier i know which webs contain the feature and could start from there with powershell, i just need to know what code to use to search the lists/libraries for this particular feature GUID.

I'm trying to rid my environment of these orphaned features so that i can successfully patch my farm to SP1, until I remove these it will not let me fully update.

Any thoughts?