This is one that Gary Clancy had in ON a few weeks ago - I tried it and it was AMAZING:

Soak a defrosted roast in a brine overnight in the fridge. The brine is made up of warm water, 1 cup kosher salt and 1 cup brown sugar.

In the morning, remove the roast from the brine, throw it in the crock pot with the usual suspects (carrots, spuds, onion). Salt/pepper/season to your liking (I just used kosher salt, pepper and a few minced garlic cloves). Add about a cup and a half of ginger ale. Cook all day.

Tender beyond tender.