Decidedly for the male psyche, here are my top five Flash games:
Crunchball 3000 - A Speedball-clone that's nevertheless fun and fast-paced. A mix of handball and ice hockey, the objective is to get the ball into your opponent's goal—by whatever means necessary. Tackling enemy players at full force seems a bit therepeutic, more so when you play against a friend. http://armorgames.com/play/3803/crunchball-3000
The Last Stand - Even with Left 4 Dead dominating the zombie-killing video game genre, The Last Stand holds it own by being more than just killing Zombies. Find fellow survivors and you'll have an easier time fixing the barrier that keeps the zombies at bay locating newer more powerful weapons. Like it's FPS compatriot, The Last Stand is pretty simple: point to aim, click to shoot, R to reload. http://www.newgrounds.com/portal/view/375622
The Last Stand 2 - The sequel to The Last Stand is similar in most respects, except you're under even more pressure as you have to get to the rescue point within a certain number of days. http://www.zombiegames.net/games/The-Last-Stand-2.html
Fantastic Contraption - Who would've thought arranging poorly drawn wheels and poles would be so addicting? Despite the simple graphics, Fantastic Contraption has that just one more round characteristic that keeps you awake as the sun rises. http://fantasticcontraption.com/
GemCraft - Yes, it's no surprise that a tower defense game has made it on my list. After all, those sort of games are Flash mainstays. GemCraft sets itself apart however, with some inventive touches. Instead of building towers to hold off hordes of enemies relentlessly trudging along a pre-set path, you build towers then place gems on them. And instead of upgrading towers into more powerful versions, you increase your destructive power by combining gems together. http://www.kongregate.com/games/gameinabottle/gemcraft