Amazon is offering the Official Nintendo DS Headset for $2.95 + free shipping for Prime Membership or any $25 order.
The DS Mic headset can be used while playing online with friends. During a battle or trade, two players can speak with each other. They must have each other’s friend codes registered for this to work. The advantage to using the DS Mic headset is that you can have a more private conversation and the Mic is closer to your mouth.
Chase Ink Bold Ultimate Rewards Business Card offers 50,000 points ($500) Sign-Up Bonus after $5,000 in purchases. The card offers flexible spending limits and requires you to pay off your balance in full each month. The annual fee of $95 is waived for the first year. I sell items on eBay and Craigslist so I applied for a business card under sole proprietorship with my name as business ID and Social Security number as tax ID.