I was convinced I had my address book quadruple-mirrored (Thunderbird, Palm, Gmail and ScheduleWorld) secured on resilient disk storage using RAID-5 with offsite backups.
However, when I came to start writing my Christmas cards, this assumption proved be to false. I think something must have gone awry during my disaster recovery testing in the summer.
Anyway, if you can remember aunties name, street name and town, you can obtain the correct postcode from the Royal Mail.
Then, armed with the full postal address, you can (probably) obtain her phone number from British Telecom so you can thank her for the thoughtful present in January.
Finally, if you bribe a call centre employee (or root around in the bins outside a major UK bank), you can also obtain her bank and credit card details to find out how much she actually spent on you this year.