I really like the new Brilliance plastic container from Rubbermaid.  I actually own a larger version and didn’t realize it was part of the Brilliance line.  The lids are truly airtight (maybe even a little hard to get off) and I like that they have a built-in vent for the microwave.  I also appreciate that the containers are made with stain and order resistant clear plastic.  They are BPA free, dishwasher safe, microwave safe, and freezer safe.