In pretending to set up a strainer for one item, really intending to use it for an item for which setting up the strainer is Weekday Work and forbidden on Shabbat: Shabbat 139b
In giving a "gift" which the recipient will have to return, in order to allow the recipient to perform a Mitzvah with the item while it is "his": Succah 41b
In bringing in produce with its chaff intact, to avoid Terumah obligation: Pesachim 9a; Menachot 67b; Niddah 15b
In bringing in produce via the roof, or backyard: Menachot 67b
In declaring one's property ownerless in order to exempt one's self from tithing laws: Nedarim 44a-45a
In order to get wine to drink after blood-letting: Shabbat 129a
In pretending to put a stopper in the side of a barrel on Shabbat for the purpose of storing the stopper, not Fixing the Barrel: Shabbat 139b
In entering a boat and falling asleep, then waking up after it crosses the water on Shabbat, and going to examine crops: Shabbat 139b
In giving something to a friend, in order that his father should take it, where his father has vowed not to benefit from him [Matnat Bait Choron]: Nedarim 43b
Declaring a first-born kosher animal to be a burnt offering while it is in utero, as a clever method to prevent it from gaining the status of a regular first-born kosher animal: Temurah 10b, 24b-25a
Salting meat atop a hide on Yom Tov, which will perforce prepare the hide for leather-working as well: Beitzah 11a
To lend money for prohibited interest: Lending someone produce valued at X, and then buying them back for less than X, so that the seller/borrower will eventually pay you back X for your loan of less than X: Bava Metzia 62b