Many problems that arise in making egg salad, chopped liver, tuna fish, etc. (Besides the issue of LOSH).
How much time is needed before or after shabbos to say it is "שכר שבת בהבלעה" (shabbos earnings included with weekday earnings).
Doing an Action to Prevent a Loss (הפסיד);
ממצוא חפציך (Mimtzo Cheftzecha): Why Do We Need Both 'Recognizable' and כוונה (Kavana)?;