I know, I know, I got your hopes up three years ago, but really, guy with a jetpack! Here! Flying around with the jetpack that he has!
...what? The catch? You're looking for some sort of impracticality with it? Oh, no no, not at all! It actually looks like a reasonable size! ...okay, fine, just two little sniggling issues.
1. You can't take off with it.
2. You can't land with it.
You have to drop out of a plane, turn it on in mid-air, and then parachute down after you're done. But surely that's not a hassle at all, right?