How to Avoid the Evening Nap?

There are days when the temptation is just too great and the eyelids are just too heavy to combat the inevitable approach of the Evening Nap. Obviously the best way to avoid the Evening Nap is to get 8 hours (or your body's equivalent) of sleep a night. But when that doesn't happen, as is so often the case for busy adults in today's society, what to do? It's a painful fight to maintain your eyes open and feign interest in conversation when your mind is screaming, "Climb into bed and shut your eyes already, you dolt!" But what may be even worse is the stupor that ensues upon waking, as if drug-induced. That's not even taking into account the grumpy disposition for the rest of the night, and the inability to fall asleep at a decent hour later on. Curse you, Evening Nap, for being so delicious and yet the demise of a good night's sleep.