Sides are the part of the meal we count on to fill in the nutritional blanks.  They are what you normally crave to have with the main dish.  In our case we have spent an inordinate amount of time working on sides because we feel that sides are what people miss and crave even more than the main dishes.  A perfect example would be the Cheddar Bay Biscuits in the picture below.  They are low carb substitutes for the high carb original and as such they fill both needs.  They are there to satisfy your craving, while at the same time maintain your ketosis.
Blueberry Cobbler - Dessert