As GitHub has recently deprecated Downloads, you might want to save all the files you've manually uploaded to your repositories, e.g. to upload them to a different place.
This command will list all download URLs for a repository:
$ wget -O- -q https://api.github.com/repos/:owner/:repo/downloads | grep html_url | cut -d\" -f4
For example, here are the downloads of my PS2rd project:
$ wget -O- -q https://api.github.com/repos/mlafeldt/ps2rd/downloads | grep html_url | cut -d\" -f4 https://github.com/downloads/mlafeldt/ps2rd/ps2rd-0.5.3.sha1 https://github.com/downloads/mlafeldt/ps2rd/ps2rd-0.5.3.zip https://github.com/downloads/mlafeldt/ps2rd/ps2rd-0.5.3.tar.bz2
To directly download all files, simply add another command to the chain:
$ wget -O- -q https://api.github.com/repos/:owner/:repo/downloads | grep html_url | cut -d\" -f4 | wget -i-
(Note that the shown commands depend on GitHub's Downloads API, which will be disabled soon. So hurry up!)