Like all superpowers, /attach is quick and easy to use. It lets you attach a file to a chat without even leaving the keyboard.
Simply type /attach and hit return. A selection box will appear with a list of files. Then use your up and down arrow-keys to choose your attachment and hit return to send it. Perfect for keyboard warriors!
By default we look in the last place you uploaded a file from, of course you can browse to somewhere else if you prefer.