The week before Christmas is upon us, so I spent last night filling in most of the remaining cracks on my Christmas shopping list. Ouch. On to the personal finance news…

Costco vs. Tiffany: Who Has The Bargain on Diamonds? Do you really want to pay $10K for just a little blue box? (@ consumerism commentary)

How Much Should You Tip? I tip about 5% no matter what, with a scale up to as much as 30% depending on the quality of service. Once, I tipped about 80% right in front of a manager who had just been deriding a new waitress who I thought was doing a good job; I did it very loudly, too, to get the point across. (@ personal finance advice)