I used to be able to turn my macbook air on, plug in an android phone, then close the lid and the phone would keep charging. Note, this was not the same as charge-and-sleep, which works all the time (like on ThinkPads). There is a link to someone describing this process here:
http://www.gottabemobile.com/2011/07/23/why-i-love-yellow-usb-ports-sleep-and-charge/
But, this doesn't work for me anymore. I've managed to replicate this with a friend's android phone on his macbook pro. He's running snow leopard, I'm running lion.
I'm guessing at some point Apple disabled this. Any ideas how to re-enable it?
I'd also be curious to hear about people's success with different platforms (i.e., iPhone, etc.)