Some outdoor adventurer currently living in a van recommends Glacier Gulch to Delta Lake (3-6hrs) off-trail:
… If you want to get away from the crowds and truly experience the rugged majesty of Wyoming’s Teton Range, you’ve gotta get off the beaten path. This is easier to do than one would think: several canyons leading into the mountains do not have established trails, and countless beautiful alpine lakes and dramatic summits are rarely visited. …
… The route ascends approximately 2300 vertical feet over the course of 1.5 miles (as the crow flies). It involves a little bushwhacking and a steep off-trail hike that’s a little too rugged for the typical tourist. Since there’s no trail up Glacier Gulch, you may come across, at most, a few groups of like-minded adventurers throughout your excursion.
Park at the Lupine Meadows Trailhead and take the main path towards Garnet Canyon. …
get the skinny on Cleansnipe – Shhhhh!… The Best Day Hike In Grand Teton National Park
besthike.com 
Looks like an amazing hike. We are heading to the Grand Tetons next month… Super excited!