It has now been eight years since the dot-com bubble burst, washing out investors in a sudsy mess.

The upside is that the painful vetting process forced the survivors to drum up viable business models and concentrate on cash flows. However, it doesn't mean that every company still standing is a rock star. There are still plenty of Internet stocks -- even successful ones -- that are ignored by Mr. Market.

There are certainly plenty of established Web companies that are worthy of your investing dollar.

  • Google (NASDAQ:GOOG) keeps growing its search engine's reach. It remains the world's undisputed leader in online advertising.
  • Amazon.com (NASDAQ:AMZN) isn't the leading online retailer by accident. As big as it may be, Amazon is still gaining market share as it broadens its categories and enhances its shopper loyalty programs.

Let's dig deeper, though. Let's unearth a few stocks that aren't as widely known in this space. You won't find any billion-dollar babies here. I will stick to companies with a market cap of at least $100 million, because we don't want to paddle too far into these uncharted waters.

Ready? Let's go.

Vocus (NASDAQ:VOCS)
Cloud computing is buzzing these days, and there's more to the booming niche than its salesforce.com (NYSE:CRM) poster child. You probably haven't heard about Vocus. It's ironic, because public relations is the company's calling card. Vocus is the leader in Web-based software for public relations management.

Despite the crummy economy, Vocus is growing. It has 3,761 subscription customers, more than the 2,911 clients it served a year ago. It expects to earn a non-GAAP profit of $0.63 a share to $0.65 a share this year, on $84.2 million to $84.7 million in revenue.

Vocus' sparkling balance sheet is also stocked with roughly $5 a share in cash and short-term investments, protecting the stock's downside until the economy does bounce back.

Move (NASDAQ:MOVE)
If you think being a Realtor has been tough over the past two years, imagine being Realtor.com. Move owns the real estate listings site, attracting 8.3 million monthly visitors to its network that also includes Moving.com and Top Producer.

Things could be better at Move. Revenue fell 11% to $54.6 million in its latest quarter. However, it has posted a profit in each of the past two quarters, and analysts see the bottom line continuing to grow from here. If Move is back in black now, the upside is huge once the real estate market turns around.

Marchex (NASDAQ:MCHX)
These aren't the best of days for the local search and performance advertising specialist. Revenues have cratered. Adjusted operating profits have fallen precipitously. The company has even been selling some of its valuable non-strategic domain names.

The upside is that analysts see revenue and earnings growing again next year. Patient investors are also being rewarded, because this is one of the few Internet companies that pay out a dividend. Quarterly distributions of $0.02 a share may seem petty, but it translates into a yield of 1.7% based on today's low price. That is likely more than what investors parking their money in money market funds are receiving.

The Knot (NASDAQ:KNOT)
As a member of the Motley Fool Rule Breakers analyst team, it wouldn't be right if I didn't include at least one active recommendation. Let's go with The Knot.

The market isn't feeling the love for the wedding planning site these days. Folks have been scaling back on their wedding day plans, if not delaying their nuptials altogether. This makes it harder for banquet hall operators, crooners, and florists to justify lofty marketing budgets.

That will change. In fact, it may already be changing. Wall Street expects The Knot to earn $0.13 a share next year and a mere $0.03 a share for 2009. Arrive early to position yourself perfectly before the bouquet is tossed.

I'll be back next week with four "under the radar" stocks in a different industry. Which industry should I cover next? Let me know in the comments box below.

The Knot, salesforce.com, and Google are Rule Breakers recommendations. Amazon.com is a Stock Advisor selection. Try any of our Foolish newsletter services free for 30 days.

Longtime Fool contributor Rick Munarriz wonders what happens if something is over the radar. He does not own shares in any of the stocks in this story. He is part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.