How much time is needed before or after shabbos to say it is "שכר שבת בהבלעה" (shabbos earnings included with weekday earnings).
Is One Allowed to Carry (With an Eruv) a Sweater to Shul for After Shabbos? Taking the Key When You Could Hide It;
Various Examples of Sifting and Straining: When Meraked May Be a Rabbinical Prohibition;