What Smells?

So, there is an unsolved mystery in my house and it is called "what is stinking up the refrigerator"? 
It smells vaguely like egg salad.  It is definitely mayonnaise or egg based. 
We just got back from a week away, and honestly all the stuff in there could have been pretty old already, so I started throwing shit away.  First I threw away the eggs and the milk and the cheeses.  That was Sunday.  Monday it still stunk, so I threw away all the peppers and onions, even the stuff that still looked okay.  But the smell was starting to take on an oniony tone so I thought maybe I had got the eggy smell wrong. 
Tuesday it still smelled so I threw away the crescent rolls, hot dogs, turkey deli meat, and sour cream (thought okay maybe the sour cream was the culprit since I found it sort of hidden towards the back and I was too scared to open it to see what it looked like because although the name would have you believe that it is already as bad as it is going to get, I am here to tell you that sour cream can get really really ugly).  Wednesday it smelled better but not as bad so I opened a carton of baking soda or whatever and stuck it in there thinking I had found the source and now it just needs to clear up in there.  However this morning it still stunk so I threw away the mayonnaise, garlic, ranch dressing, and horseradish - all things that probably should have made the first toss.  I also found an orange from when my parents visited the first week of September so I threw that away too.
Today when we got home I optimistically opened the fridge and thought it smelled better.  However, horror of horrors - when Adam opened it later I got a whiff of the offending egg salad smell from all the way in the living room which is terrifying. 
This leaves the burning question - what the hell is stinking up my refrigerator? 
My refrigerator now resembles my college refrigerator - there is beer and ketchup and relish and Dr Pepper and that's about it.   
Horrible Fact - I can't possibly cook anything that currently resides in that refrigerator or freezer knowing that it may be the source of the gross egg salad smell or that it could have taken on the egg salad smell itself, which means that until we start over with all new food - I can't cook.     Did I say horrible fact?  I meant oh happy, happy, happy me.