Anything that can go wrong, will go wrong. (Is that so? How come other people's lottery never ends up in my pocket?)
No matter how long or how hard you shop for an item, after you've bought it, it will be on sale somewhere cheaper.(Simple, return the old one and buy a new one)
The other line always moves faster.(Not the case when I am on my way to work)
When in doubt, mumble. When in trouble, delegate.(The worst case is that you are the one who are being delegated.)
Anything good in life is either illegal, immoral or fattening.(I will add one more: unattainable.)
Murphy's golden rule: whoever has the gold makes the rules.(not true. A Smith&Wesson beats gold)
Nature always sides with the hidden flaw.(I hope this is not about how I look)
A Smith & Wesson beats four aces.(not true. whoever has the gold makes the rules)
In case of doubt, make it sound convincing.(sound convincing? How about this: if I can't convince you, I will confuse you; if I can't confuse you, I will dazzle you.)
Never argue with a fool, people might not know the difference. (This one is the best. I will print it and stick it at the rear bumper of my car)