I've been looking for inspirations on ways to use cards that feels like it's working outside those cards' expected parameters/use-cases. Things that feel like they hit strategies that WotC might not have thought about when printing the cards.
For instance, one of the most popular expressions of this is the open secret that Tivit, Seller of Secrets actually functions better as an artifact-combo commander than as a voting commander - every ETB or combat hit makes 5 artifacts, guaranteed, which makes Time Sieve combos easy.
Or, in terms of decks I've brewed/been brewing, Zevlor Elturel Exile as a poison-proliferate deck. Doesn't work great, but the idea is to try and spike the board with multiplied proliferate triggers, so I can tick people up by 3 poison per "single target spell plus proliferate as an upside" spell. Turns out that people just focus you and your commander out of the game pretty much immediately if you try that, but I digress.
Or, using Mutate as a mechanic not to try and actually proc on-mutate effects, but just to strip "legendary" off cards that are balanced around it as a mechanic, like Kiki-Jiki. Mutate him into a nonlegendary, and you can infinitely multiply him during your prior opponent's end step, and overrun the board during your turn.
It's effects like these that I really enjoy exploring, the cases that make people stop and say, "Wait, it works like that?" or, "Wait, you did all that just to do this?" It scoops a lot into the art form that is jank deckbuilding, and I'm curious to know what little corners of the MTG design-space you all have found funny little interactions in.