Any start-up that is:
1. >24mo old
2. Hasn't turned a profit
3. Still going after funding rounds
4. Has a valuation in the millions of $$$
...those are the inflated .com bubble of today. Those companies that say "fail fast" and "pivot" to a new "paradigm"... those companies that do not grind out a profitable idea and burn through stacks of cash only to fold up and leave VC firms and angel investors high and dry. Those are today's monetary drag...
You want to know the biggest? Youtube. Never had a profitable quarter in the history of the company, even after Google bought them. A gigantic money-suck.
Fitbit / companies that make activity trackers are at least producing a product and are financially stable enough for the FTC to allow an IPO. Those aren't the bad companies regardless of what you think of their product. I think C.Crane is slinging more snake-oil online than any of the activity tracker companies.