Want to take a look around Yellowstone and Grand Teton National Parks, but just can’t get away right now? There are webcams all over both Yellowstone and Grand Teton that give you a glimpse of what’s going on in the parks.
(Obviously these don’t work at night because it is too dark to see anything!)
Yellowstone National Park:

Electric Peak and the Yellowstone River from Gardiner
Electric Peak from Yankee Jim Canyon
Mammoth Hot Springs (original)
Grand Teton National Park (and nearby):

The west side of the Tetons, from Idaho
Tetons from Spring Creek Ranch
Southern end of Grand Teton National Park