How can I easily make screenshots of screen regions on Arch Linux with i3 WM?

About a month ago I switched from Ubuntu 14.04 LTS to Arch and I'm quite happy with this decision. However, I miss some features with my new distro, especially Shift+printscr which in Unity allows selection of a screen region to be captured. I use i3 WM. So, my question is: how can I configure Unity-like screenshot behaviour to be able to snap screen regions or windows with a keyboard shortcut or something (without digging into window id and console stuff)?