Flickr causes crashes with Aperture
There's is a cooler solution if you are a bit into computers.
You can create an automator script and link it with Aperture. When the connection with flickr is opened, the script will disable sleep on while uploads are pending. Or similar. Google for "pmset", "sleep", "mac", "automator", "script" etc.
|Christine by JP Zanotti|
from Car wreck
|Fangorn Forest by cand1d|
|Yosemite Falls with Moonbow by Jonathan Shapiro|
from Best Landscape of the Week 4