Phineas and Ferb Accessories ...The party is not complete until you add Phineas and Ferb party accessories. Make sure to look at KidsPartyWorld.com's accessories department including Phineas and Ferb blowouts, stickers, hats as well plastic accessories such as Phineas and Ferb 16 oz. souvenir cups which make a great birthday party keepsake, and useful party food serving bowls. After the birthday party, consider sending Phineas and Ferb thank you notes to your entire guest list. No matter what you choose, a Phineas and Ferb accessories will make a great addition to your birthday party list.