Bento boxes are an easy solution for me when packing lunches. They offer an easy way to manage portions, tend to be sturdier than Tupperware, and are often cuter to boot. But because of the size and shape of most bento boxes, packing a freezer pack or something else to keep food cool just doesn't work out so well. The Gel-Cool Bento Boxes seem to have solved that problem, however. They come with a lid with a built-in gel pack that you can freeze overnight. Then, in the morning you can pack your bento box like normal. Cover it with an inner lid, which ensures that your food stays put, and then place the cold lid on top. Provided you take off the lids first, the box is even safe to put in the microwave.
The Gel-Cool Bento Boxes are sized for adult meals, measuring 7 inches by 3.25 inches by 4.75 inches. Each box holds about 2.5 cups of food and they're created to be a two-tier set of boxes. You can carry just one of the boxes easily, though you should use the band that comes with the boxes horizontally if you're only carrying one. The Gel-Cool Bento Boxes are available in pink, gold, green, and blue. They're $36.