As far as we know, Lego has officially released only USB flash drives in the form of generic Lego minifigures (aka minifig). With the popularity of minifigs, Lego is likely to make a fortune should they ever decide to expand this to include popular licensed Lego minifigs. Meanwhile, you can get your hands on customized Lego Minifig USB Flash Drive featuring a wide variety of popular pop culture minifigs from Marvel and DC superheroes to Star Wars to Lord of the Rings.
Many of these Lego Minifig USB Flash Drives are made from the minifig keychains so it is really convenient to bring along a spare USB drive with you by hooking it up to your bunch of keys or just attach it to your bag.
One thing to note is that stuffing a USB flash drive mechanism into the body of the minifig means that the legs no longer fit. Most sellers custom build a set of non-movable legs that act as a cap to protect the drive. These legs don’t look as good as the original of course but until Lego decides to come up with their own versions, these will have to do. Some sellers replace the legs with a transparent cap that can be attached to standard Lego studs.
Storage sizes varies from 4 GB to as big as 64 GB. Some come with USB 2.0 drives and some come with the much faster USB 3.0 drives.