Evan Blass (aka evleaks) just leaked a alleged cover for the Galaxy S6 edge+ which features a physical keyboard overlay. This would basically act as a replacement for touch-based typing into a physical QWERTY input method (including keys for the home, recent apps and back functions) and it would likely protect the lower part of the screen. This is a pretty unusual accessory (note how the UI has adjusted to the upper part of the display) and Samsung usually doesn't make such covers.
The Galaxy S6 edge+ is going to be unveiled next week at the Unpacked event in New York, and this leak just made things interesting, while also ruining yet another one of Samsung's surprises if it is indeed the real thing.