9. Battery Stem
Battery Stem was created by South Korean startup PiBike, the water- and dust-resistant Battery Stem is simply a 100-mm handlebar stem with an integrated 10,000-mAh battery pack that can be removed for charging. According to its creators, on a full charge it can run a typical smartphone for about 15 hours.
If you’re interested in getting a Battery Stem, it’s currently the subject of a Kickstarter campaign. A pledge of US$189 will get you one, when and if they reach production. The planned retail price is $249.