For those of you who have Citi credit cards, you might try asking for a credit line increase. They seem to be getting a little more liberal with the preapproved CLIs. Here's a FatWallet thread about it.
Login to your account online, move your mouse over "Manage My Account" and click "Credit Line Increase Request." Previously, Citi required having the card for 6 months before being eligible for an increase, but I got an increase on a card I've had for 5 months.
I got an $800 CLI on my Driver's Edge card, and a $1000 CLI on my mtvU card. Last month I got a $500 increase on my Dividend card.
I also received another increase on my AMEX Blue, this time to $4600. In 1 month with AMEX I've gone from $2000 > $2400 > $4600.
So give the Citi thing a shot. Be warned, if you're not preapproved for a CLI, you'll be shown a form to fill out. If you fill out this form, you'll probably get a hard inquiry on your credit report.