Very cool. I'm not a moderator or anything but I don't think you have any trademark concerns to worry about. If anything, Hive, Ecency, LEO, etcetera should be thrilled you're promoting their business.
Can you give me an estimate how much it would cost to ship one of each color to London?
RE: How about a Hive t-shirt? // Que tal uma camiseta do Hive?