Windows: Layers of dirty film on windows and screens provide a helpful filter against harmful and aging rays from the sun. Call it an SPF factor of 15 and leave it alone.
Cobwebs: Artfully draped over lampshades reduce the glare from the bulb,thereby creating a romantic atmosphere. If someone points out that the light fixtures need dusting, simply look confused and exclaim "What? And spoil the mood?" (Or just throw glitter on them and call them holiday decorations.)
Pet Hair: Explain the mound of pet hair brushed up against the doorways by claiming you are collecting it there to use for stuffing hand-sewn play animals for underprivileged children. (Also keeps out cold drafts in winter.)
Guests: If unexpected company is coming, pile everything unsightly into one room and close the door. As you show your guests through your tidy home, rattle the door knob vigorously, fake a growl and say, "I'd love you to see our den, but Fluffy hates to be disturbed and the shots are SO expensive."
Dusting: If dusting is REALLY out of control, simply place a showy urn on the coffee table and insist that "This is where Grandma wanted us to scatter her ashes."
General Cleaning: Mix one-quarter cup pine-scented household cleaner with four cups of water in a spray bottle. Mist the air lightly. Leave dampened rags in conspicuous locations. Develop an exhausted look, throw yourself on the couch and sigh, I clean and I clean and I still don't get anywhere." As a last resort, light the oven, throw a teaspoon of cinnamon in a pie pan, turn off oven and explain that you have been baking cookies for a bake sale for a favorite charity and haven't had time to clean... Works every time.
Another favorite, I think from Erma Bombeck: Always keep several get-well cards on the mantle so if unexpected guests arrive, you can say you've been sick and unable to clean.
( I copied this post from here: http://www.emmitsburg.net/humor/daily_additions/2009/nov/2.htm)