Numbers, numbers, numbers
I'm betting that you can remember a lot of numbers, right?
If you're anything like me, you'll remember the license plates of your Dad's cars from *cough* 30 years ago. (btw, they were OVO 914F and VFJ 158J - I wonder where they are now?)
Today I realized that I can remember passwords that I'm sure non-geeks would have a hard time remembering. I open RDC and see a list of IP addresses, pick one and have to remember some super-secure password that goes with it. I'm frankly surprised I can remember that password J8k3112p! goes with IP address 136.54.89.345.
Yet, I frequently forget things that my wife tells me. 
I'm always in trouble for going to the store on an emergency mission for whole wheat pasta and coming back with a car magaine, a gallon of milk and some chocolate cookies (ok, not true, the cookies get eaten driving back to the house).
There was a famous incident, often told with glee by Tara, where I was sent to the store while on holiday at my sisters house in Australia. Strangely I can't remember what I was supposed to get, but it wasn't the icecream that I returned with. Or was it milk.. I forget.
But just ask what my license plate was on that Toyota we owned in 1993. SSN? pah! Drivers license number? Of course!
(Funnily enough, google's toolbar autofill feature robbed me of the need to remember credit card numbers, but my wife can remember hers because she types it in online so regularly. Now THAT is scary when you discover that I can tell you.)
I wonder what the name for this kind of selective memory is...and while you're at it, what is it called when you frequently think one word and another one comes out? Senility? I'm always calling my kids by the dogs names, or saying "pass me the cushion" when I meant "salad".
Ah, programmers and their diseased minds...