I made a tad bit too much rice, so I thought well I could freeze some for speedy lunch packing. Instead of using my onigiri molds I decided to just shape the rice with my hands and let Diva dip them into sesame seeds. That way they would be smaller and fit better into the bentos and have some color to them. I did wet my hands occasionally when they got too sticky. This picture is of the rice frozen and ready to be put into a freezer bag, I do have a Foodsaver, but zip tops are easier when you want to take out a few pieces of food at a time. Next time I will freeze these on wax paper instead of a plate, they were kind of a pain to get off once they were frozen. When I am going to use these I heat them up to restore texture. They are soft and still taste good. I wouldn't put them into a bento frozen and expect to be able to eat them without heating first though, the rice would just be hard.
Edited to add-
you can season your rice with a little salt, sugar and rice vinegar or tamari or add flecks of nori, sesame seeds, dried fish etc. Or form them plain.