You can store these grains in a bucket, and move your fingers and hand around in them. Pitchers do this to strengthen their hands, as do grip strength fanatics. Check out "Mastery of Hand Strength", the seminal volume on this!
This works for rice, but I'm not sure about the things you have. Sew it into a small cloth bag or a pillowcase, then warm it up in the microwave; then you have a hot pack for aching muscles or whatever else.
Rolled oats make a great facemask- mixed in with water and clay if you need it to be stickier. Otherwise just make it thick enough to splodge onto your face- leave it on until it dries out, then wash off with warm water. It tightens up pores and leaves the skin really soft!
Rice can be used for salt shakers to stop them blocking...
I use dried grains in a small bowl as my incense holder. Im using thin, long sticks of incense and the only way i can get them to stand upright and have their ash fall down right into the bowl is to have something like buckwheat, oats, rice, etc as a bedding. Works like a charm.