The weekly sugya on the parsha on the topic of קידושין בחמץ דרבנן and a discussion of the concept of "cheirus" here.
A series of questions I sent to HaGaon Rav Chaim Kniyevski Shlita, here [through a chavrusa and close friend who is very close to Rav Chaim [so I am only one person away from being close to the Great Rav Chaim Shlita!:-).