We eat a lot of rice at our house (husband is allergic to wheat products), so there's almost always a little leftover rice. I like to top it with bits of leftover pork or chicken, add a handful of frozen veggies, season, stir, and freeze in lunch-size portions. Rice, plain roast chicken, a dollop of hunan sauce from a jar, plus frozen peas, and it's a kind of Chinese lunch. :)

I also like to make chicken and black bean burritos to freeze. If you don't have fajitas (the bready wrap part) to make them, you could put the seasoned chicken and black beans in pita bread halves.

My favorite frozen lunch is one I cook from scratch just for myself: dried pinto beans cooked with a bit of ham, sweet potatoes with cinnamon and a drop of maple syrup, cooked mixed greens, and a piece of cornbread. It's a Deep South favorite.