Dude you can do -everything- with a sandbag, and stuff that you basicly only can do with a sandbag.
Shoulder it from the ground for reps. Shoulder and press it. Clean it and press it. Clean it and throw it explosively. Backsquat it. Overhead squat it. Zercher squat it. Bicep curl it. Row it.
Remember that you never lift using any handles or anything else that makes it easier. You always grab it by grabing the cloth, thats half the purpose of the excersice and will turn basicly every excersice into a great grip builder.
With that said a nice little excersice to do is "snatch and catch", snatch it explosively by holding it like described, instead of "racking it", you let it fly as high as you can (it should be heavy so the flight dont get more then a few inches) and on the down way you catch it and do a zercher squat with it. (do you understand the explanation? its a killer excersice..)
Other thing that is good to do with the sandbag is "finisher" type workouts. Bearhug the bag and walk with it, overhead press it and walk with it, curl grip and walk with it, etc. This is best done as a finisher to any workout. Push yourself on this one, its just as much a mental strength builder as it is a physical.
Another option is to throw the sandbag over your shoulder and sprint upp hills with it.. (be sure to prepare yourself for this one, it can lead to problem with your joints otherwise..)
I have only started to list shit you can do with a good heavy sandbag, as you see the posibilities are endless. You will need different weights of sandbags to do different type of excersices.
I basicly have to credit Ross Enamits book "ultimate training for the ultimate warrior" for all the stuff I wrote above, its a great book on the subject, you can get it at
www.warriorforce.com I also hear that Dinosaur training is the book to have on the subject but I have not read it myself.
Good luck dude!