Samsung has just announced that a wireless charging cover and pad are now available for the Galaxy S4. Samsung had originally annouced that wireless charging would be coming to the Galaxy S4 when they launched the device a month ago, but now the wireless charging has actually materialized.
If you already have a Qi-compatible charging pad, you're in luck as Samsung has made use of the Qi standard and is selling the cover and pad separately. The cover can be had for $39.99 and the pad can be had for $49.99. If you need both, it will set you back $90.
It's good that Samsung made use of the Qi standard as multiple other devices already make use of it. It makes that investment for the charging pad just a bit easier to swallow.