Question: where does Eclipse store the list of files it opens on startup?

Background: Having installed a plugin into Eclipse which promptly crashed, my Eclipse workspace is in a bit of a state. When started, the building workspace task pauses indefinitely at 20%. Before I uninstall the plugin I want to give it another chance. I have a feeling that the reason Eclipse is pausing is because of a file which was opened when it crashed, which it tries to reopen on startup. If I can stop this file from opening on startup there's a chance I may be able to coax the plugin to behave. The problem is I have no idea where that list of files is persisted between runs of Eclipse.

...a second before I posted this question, I realised I could just delete the file causing the problem (duh). However, the search has frustrated me enough to want to find the answer.