A very useful curl switch that I discovered, resume of partially downloaded file ! -C or --continue-at <offset>. When offset is "-", curl will use the output file to figure out the offset.

curl -C - -o "some_file"

It will basically get the size of "some_file" and use it as an offset when making the HTTP request, similar to wget --continue.

Very useful to download a file from a unreliable network and when you need all those security cookies. To get the cookies I use "Copy cURL" from Network pane of Chrome's "Developer tools".