Not to mention, it gives one ammo to use in their attempt to teach people that the world is really only 6000 years old vice several hundred million!
I'm a young-earth creationist too, but I've never had much luck arguing creationism from the Bible, especially not to non-Christians.
Bishop Ussher's tracking of the genealogies in the Bible is a commendable piece of work, but I remember noticing at least two holes in it when I studied it--places where he had to make assumptions because the hard data wasn't there. Of course, those assumptions are not going to make five or six orders of magnitude worth of difference (the age I've always heard for the earth is around 2 billion years, not several hundred million), but they're certainly weaknesses.
When I'm arguing with Christians, I prefer to use the philosophical differences between Genesis and evolution rather than the scientific ones; they're less arguable. For example, Genesis says that there was no death before man's first sin (and that before that sin, all animals were herbivores); evolution says that death was around millions of years before man was. (Extra credit: where is the very first death in the Bible recorded? It's a trick question.) Also, Genesis is very particular about the order in which things were created (first day, second day, etc.), and it's a markedly different order than that of any evolutionary theory I've heard. There are other anomalies: for example, light was created on the first day, but the sun and the moon weren't created until the fourth day--after the earth was already covered with green things.
The biggest problem, I think, in the whole Origins argument is the subtle lie that if you push hard enough, creationism and evolutionism can be reconciled. They absolutely cannot, and it's important to realize that from the outset.
When I argue with non-Christians, I like to leave creationism completely out of the picture and simply talk about the increasingly real limitations of modern evolutionary theory. Being a computer geek, I generally start out with some of the serious information-theory concerns it raises.
But I didn't mean to get
this far off topic.
Okay, you have a hard time remembering the anniversary, etc. So, what does it mean if one can't remember any of the gift ideas that their wife hands them every other day of the year?
In technical terms, I'd guess it means one is hosed.