A really nice snack is Ryvita (HexB) (multigrain is my favourite variety) with laughing cow cheese triangles (HexA) spread on them. If you use them as your Hex's, then there's no syn there.
Or Ryvitas again, but get the virtually fat free cottage cheese and mix with chopped cherry tomatoes, spring onions, peppers and a sprinkling of black pepper and put that on the Ryvita. Again, if you use the Ryvita as your HexB, it's another syn free snack. And a good choice for when you really fancy something savoury.
Make up a pot of soup and freeze back some portions. There are plenty of recipes for soups, but most are easy to make and are free if you don't add oil, cream, etc. Heat up a bowl when you fancy a free snack...