The fall of Crocs (NASDAQ: CROX) as a momentum stock has been just as spectacular as its rise.

After a drop of around 40% in trading this morning, shares of Crocs have fallen below their IPO price -- after closing at a split-adjusted price of $12.58 on the first day of trading, Crocs shares are down to $10.60, giving investors who bought on the first day a total return of about about -16%. That's amazing because at the company's high of $75.21 reached on Halloween of 2007, investors were up more than 500%.

I've always thought Crocs was a garbage stock. In February of last year, I wrote about Crocs as one of three retail fad stocks to beware of. Based on my prior posts on Crocs, here are the lessons I think investors can learn from watching the decline of Crocs' share price:

On a final note, Crocs' beaten down share price might finally make it worth another look, now that expectations have been moderated.

By the power vested in me by AOL, its corporate parent Time Warner Inc. (NYSE: TWX), and those associated with the above entities, I declare the Heelys Inc. (NASDAQ: HLYS) fad to be over.

Mr. and Mrs. America, you will no longer be forced to dodge hordes of tweens flying around the mall in their God-awful and unsafe wheeled sneakers thanks to my sinister and cunning plan. I am urging my fellow thirty-something suburbanites to buy Heelys and roll on them in public. Once kids see how dorky we look "heelying," they will surely give up their expensive, trendy footwear, which they will grow out of sooner rather than later.

Perhaps the market is anticipating my plan. Shares of Heelys, which was one of the most highly touted IPOs last year, have slumped about 3% this year. Parents everywhere should rejoice. The company, unlike Crocs Inc. (NASDAQ:CROX), is a one-trick pony, and fads do eventually end.

BloggingStocks writer Georges Yared wrote an excellent piece yesterday in which he wondered whether Crocs Inc. (NASDAQ:CROX) is the next L.A. Gear. If it is, that is not good news for CROX shareholders. As Yared writes, L.A. Gear rose to prominence in the mid- to late-1980s, and faded into oblivion during the 90s (although it is currently working on a comeback). Clothing, particularly when marketed to the teen demographic, is probably the most fickle industry on the planet. As Jerry Reed sang, "When you're hot you're hot ... when you're not you're not."

Investors should tread extremely carefully when investing in hot clothing products. If the popularity of the product wanes, so will the earnings, and so will the stock price. Predictably, many of these companies attract the attention of that much maligned group of investors known as short-sellers, who seek to profit by betting on a declining stock price.

Here's a list of some of what I consider to be the top "Retail Fad" stocks going right now. As a word of warning, I am not saying all these products will turn out to be fads: