If you thought ETF and ETN mania was out of control a few years ago, then you have another thing coming.

There are well over 1,000 exchange-traded funds currently listed on U.S. stock exchanges and more than a hundred additional exchange-traded notes. In short, your investing choices are absolutely overwhelming. For instance, let's say you wanted to invest in commodities. If you pulled up options for commodity investing (oil, natural gas, and precious metals), you'd find well in excess of 100 possible ETFs and ETNs.

ETFs are big business, and the issuing companies behind these funds understand that all too well. According to Deutsche Bank, 2011 brought in record cash flows of $163.8 billion to the global ETF industry. Deutsche also estimates that ETF net assets could rise by 15%-20% in 2012, resulting in $137 billion to $190 billion in net new investor inflows.

With that in mind, sometimes these companies don't exactly have investors' best interests in mind when bringing ETFs and exchange-traded notes to market. Right now, the only battle being waged among ETF issuers is who can deliver the most volatile product.

Take, for example, these newly issued ETNs from VelocityShares -- a firm that has made a habit of picking on traders with a penchant for gambling their money away:


Expense Ratio

VelocityShares 3X Long Brent Crude 1.35%
VelocityShares 3X Inverse Brent Crude 1.35%
VelocityShares 3X Long Natural Gas 1.65%
VelocityShares 3X Inverse Natural Gas 1.65%
VelocityShares 3X Long Crude Oil 1.35%
VelocityShares 3X Inverse Crude Oil 1.35%
VelocityShares 2X Long Copper 1.35%
VelocityShares 2X Inverse Copper 1.35%

Source: IndexUniverse.com.

Not only does daily rebalancing effectively destroy the long-term value of any of these investments, but the expense ratios of 1.35%-1.65% are significantly more than PowerShares' average expense ratio of 0.95% for its leveraged products. Keep in mind that ETFs often pay a dividend; ETNs usually do not. So don't be expecting a dividend anytime soon from these highly levered investment vehicles.

Simply put, buying into gimmicks like these is akin to committing investing suicide as I see it. There are far better ETF choices that could satisfy your urge for diversification than what VelocityShares is attempting to get you to buy into.

If you're looking for copper exposure, the Global X Copper Miners ETF (AMEX: COPX) owns shares in 33 separate companies and is yielding 3.7% over the trailing 12 months. If oil is your interest, the United States Oil (AMEX: USO) and the lesser-followed United States Brent Oil (AMEX: BNO) ETFs are your best bet to mirror the price of West Texas Intermediate or Brent crude, at least over short periods of time. For natural gas, the iPath DJ AIG Natural Gas (AMEX: GAZ) ETN offers a lower net expense ratio than some alternatives, but unfortunately it lacks a dividend. That's why, as I mentioned in "It's Time to Buy Natural Gas," I prefer the iShares S&P North American Natural Resources (NYSE: IGE). Combining all natural resources into one basket, this fund yields 1.2%, owns shares in 157 different companies, and boasts a nominal 0.48% expense ratio.

This is how you successfully navigate the ETF market -- not by throwing your money at issues that play on volatility's heartstrings. Do yourself a favor; when you come across a heavily hyped double or triple-levered ETF, run the other direction.

Do you have an ETF mistake you now regret? Tell me about it in the comments section below.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.