I ended up babysitting a Hoary Bat for a couple hours last weekend. We found her when cleaning up some ivy off a house - I ended up watching over her until she was awake enough to fly off and find a new roost.

And the happy ending! Just as we were going to put her in a safe spot on the roof, she had warmed up enough to fly off. She circled the yard and then landed on this vine and did a very good impression of being a dead leaf.