How do I work out the use-by dates for my own cooking? If I sort my fridge by 'eat by' date, what is the best way of dealing with food's I've cooked, or partially cooked, myself? 

In my fridge there are such delights as: 


thrawed from frozen strawberries for the baby
Seiten loaf, made in the last day
several different types of leftovers. 


...and it occurs to me I don't know how to work out the 'eat by' dates on any of the dishes we've made ourselves. 

I'd like to know some good rules: excellent answers might include: "I run a bakery and this is the situation that the FDA told us we had to go by" but I'll take any information there is...
The US FDA has a handy Refrigerator and Freezer Storage Chart that might help you.  In general your "leftovers" have a 3 to 4 day shelf life...I would think that includes your thawed strawberries.