I'm going to be moving out of my apartment and going travelling for a few months at the start of May, so I'm currently going through the contents of my pantry and fridge and using up a lot of the food that we won't be taking with us. However, you don't need to be doing something so drastic as this to clean out your pantry: ideally I've found that you should do it about every 3 months, or every season.
Go through all your sauces. Is there anything that is past its best before date and should be chucked (or used up immediately)? Is there anything approaching its best before date and should be used soon? Is there anything that you've completely forgotten about and will now plan to use? Are there any bottles that are virtually empty and have been put back (by someone else of course) and should be chucked out?
Go through all your dry goods. Is there anything that is past its best before date or has pantry moths and should be chucked? (I've found some sticky traps that work great for moths.) Is there anything that has been untouched for ages and you should plan some recipes that uses it soon? Are there any opened packets that haven't been put into jars and should be done now?
I find it's good to take everything out of the pantry and clean down all the shelves before putting everything back. (This also ensures you don't miss anything.) Do the same with the fridge (although ideally do it more often, and before you do a grocery shop when you don't have many fresh items in it).
At the moment I've got a list of meals and recipes (from having risottos and soups to use up the stock in the freezer to sticky date pudding) to cook in the next month. And a great bonus is it also means I don't need to spend much money on grocery shopping, leaving more money for travelling!