Nvidia has been using the same model numbers for mobile/desktop with Pascal, unlike previous architectures where they gave mobile and desktop non-comparable model numbers (e.g. desktop 970m was roughly equivalent to a desktop 960 GTX). So if someone builds a laptop which can power a 1070 Ti, it should show up.
Powering it is the catch though. Right now laptop AC adapters (power bricks) top out at around 180 Watts. High-end gaming laptops consume more than this when gaming (GPU + CPU + everything else). Consequently, they slowly drain their battery when gaming, even though they're plugged into AC. You'll get maybe 4-5 hours of gaming out of them before the battery is drained, then the GPU and CPU will throttle back to keep power...