A while back, Japan got these neat Mario / Luigi hat pouches. Some people might recognize them, as they were on the European Club Nintendo for a long time. It would seem that the US Club Nintendo has gotten Luigi in honor of St Patrick’s day. Additionally, the whole site is decked out in green, so you might want to check it out.
If you want to get one, it will cost you 450 coins. However, you might want to wait for Mario, though there’s no word on when or if he will appear too.