https://transfer.sh which I built because I needed it myself, now being used by hundred thousands of people a month and http://slackarchive.io used by 500 slack teams.
transfer.sh is easily one of the best file-sharing website I've used.
when I recommend it to others, they find it _counter-intuitive_ to use, maybe because of them not being comfortable with the command line. now it has a drag/drop interface, so, that's _good_ (i guess).
one "issue" that I do have with it, is that downloads aren't resumable/pause-able or you can't see actual download progress. Is this a limitation or was it built that way ?
Not sure the code is production ready, but similarly, dro.pm is a small thingy that has a command line option to share files. The links expire automatically so there's no abuse headache and it allows links to be single characters most of the time (eg. dro.pm/v).
You can even edit links afterwards, for example to remove content you know the other person already opened.
Additionally to files, it also dupes as a URL shortener and as pastebin if you paste text.
