Turkish Get-Ups (TGU's), Windmills and Swings. Who needs kettlebells? In fact, I worked out that you can also use your Brute Force Sandbag just like a Bulgarian Bag too (although being this awesome may well void your warranty).
I used a 35kg sandbag with the following grip:
Try 5-10 repetitions of each exercise, repeated for 2-3 sets.
The Turkish Get-Up is a tough, full body movement that will do great things for your core and shoulder strength. Start off lying flat on the ground with the sandbag held in one arm above your chest. Then stand up, keeping that arm straight throughout the movement. This can be achieved in a few different ways - but I recommend "rolling out" to the side (up onto your elbow) and then standing up in a lunge movement.
The Windmill is another great core exercise that you rarely see these days. Simply hold the sandbag overhead in one hand. Then, keeping your legs straight, reach down towards the floor.
Plenty of people do Swings with Kettlebells but it's also possible (and much harder) with a sandbag. Grip the bag at either end and hold it between your legs. Using a powerful hip drive, start generating momentum with the bag. Be sure to keep your arms relaxed and aim to swing the bag up to at least chest height. Keep your spine in neutral throughout!
Or single handed:
And Just When You Thought It Couldn't Get Any Better!
Who needs a Bulgarian Bag?