Some things can withstand the test of time, like The 40-Year-Old Virgin (still great every time I watch it). But opened/ leftover food and starving pets dont do that very well, and just in case you are lacking in short-term memory (Snoop Dogg complex) then the DaysAgo is for you. Its a digital counter that clocks how many days ago something was opened/ or packaged. They come in multiple colors and magnet or suction cup models for cans and plastic containers. Two for $10 here.