I'm not sure if this counts, as the trade was offered to me, I didn't really do much besides click the "accept" button.
Two years ago - 2006. I was offered Crawford, Rollins and Sexson for Carlos Lee. I then flipped Rollins (as I had drafted Reyes in the 7th RD) and landed Vlad straight up.
The owner that offered me the trade did end up taking 1st though - i took 2nd.
I've got a few: Drafting Nate McClouth pick 199. It was kind of early, but I wanted to make sure I got him.
Trading Ricky Weeks, Carlos Lee, Nick Swisher, and Josh Beckett for David Wright, Conor Jackson, Chone Figgins, and Fausto Carmona a week before the season.
I'm starting to lean towards drafting Soto in the last round of my money league this year. Of course, I am saying this after he demolished a ball that should have been a homer either way, but he had to run around the bases for it to count.
Unless you've only been playing for under 3 years, I find it hard to imagine people really remember these best/worst moves unless it either happened this year or it's a keeper/dynasty so it has carryover effects.
Picking up Ryan Zimmerman, Dan Uggla, Hanley Ramirez, Justin Verlander, Jonathan Papelbon, Josh Johnson, Francisco Liriano, Cole Hamels, Jered Weaver and Takashi Saito in 2006.
Haha just kidding.
But anyway, yes there are too many of mine to mention.