Gulp/Gulp Alive Storage
I pulled out some Pork Crawlers I opened last year and then put into a small zip freezer bag and stored in my tackle bag in the closet. They were still like new and I caught fish on them. Gulp is so messy. The Pork Crawlers are a LOT more durable and you can cut them down to any size you want.
I do like the thermos idea though, but probably any container with a gasket would work.