Me and my dad are the same sort of way with numbers as you are -- it makes for remembering PIN and phone numbers all kinds of fun. The irony is, I went on to do pure math in high school (okay, so it's all agerbra, very little numbers) and was still horrible about it, but I'm great at working out money in my head while at the check out.

But see, that's odd; I can remember PINs and phone numbers just fine. It's money at work I'll eff up, and I can't work out change very well at all unless it's an easy number.