JudasIscariot: Why not just download while you sleep? :D
Because the GOG Downloader has a tendency to choke if you queue a few GB-heavy games and every time I've tried that, I woke up in the morning only to find the Downloader in some sort of frozen state (it would be responsive but wouldn't go online) while at least half of the games were still waiting to be downloaded. Worst part was that it'd usually require to cancel all downloads, logout, terminate the Downloader, restart it, re-login and add the games back.
Having learned my lesson, I now run the GOG Downloader on my laptop and use my Desktop for other online activities - this way I manage to "steal" some of the bandwidth from the Downloader and do online stuff while still keeping an eye on the downloads ;P
I generally like the Downloader because of the speed it manages, but it definetely needs improvement in a few areas.