Yesterday, i played a non-engine game where i opened Masquerade and Watchtower (Shelters game). I was lucky enough to trash 5 Coppers through Mint early on, and soon after that, i happened to hit $7 with Watchtower in my hand, and out of coincidence, i decided to buy a Masterpiece. The Watchtower-reaction window popped-up, and then i realised how cool what i just did was!
Revealing Watchtower to Masterpiece and trashing it.
Revealing Watchtower to the 4 Silvers gained, putting them on top of my Deck.
And my next turn was a Province.
Now, i'm kinda sure that i'm not the 1st one who notices this wonderful interaction, but not everyone would think of it just like that, so i felt like i wanted to share it.