Discovered what the horrible smell in my kitchen was, finally - we came home after a weekend away, leaving the thermostat on 80, to discover something in the kitchen smelled bad. Couldn't find it - wasn't the trash can, wasn't anything in the sink, even ran hot water and extra detergent down the sink in case something was caught in the drains. Nothing. Until I realized that under the pile of empty grocery bags was a TOMATO. Oh, my, lord. I've found a stray potato that's escaped under something until it rotted before, and let me tell you, NOTHING smells worse that rotten tomato. Especially when it's leaked and there's rotten tomato juice all over the counter, under plastic bags. Wow.
Thirty minutes of scrubbing and a whole bag full of nasty paper towels and antibacterial wipes, and my kitchen is fit for humans again.