As

Warren Buffett

likes to say, it's only when the tide goes out that you see who's been swimming naked.

And "naked" pretty much sums up the plight of a lot of little tech companies right now. With business plans calling for years of exponential growth fueled by other people's money -- but no more money to be had -- they're left with two options: Generate cash internally (dream on) or find a deep-pocket backer. Those that can't do either will go the way of

boo.com. The relative few that can will at least get a chance to see where their business models and management skills take them.

Obviously, companies want to be in the second group. So let's think about how to find them.

One simple way is to screen for fast growth and a big cash balance. If a company is flush from a recent initial or secondary public offering, it has a year or so to do its thing without sweating the market. The March 20

Barron's

ranked 207 Internet companies by the likelihood they would burn through all their cash. You can probably outperform the market by simply buying the 10 least likely to burn through their cash reserves and shorting the 10 most likely to do so.

But cash is only part of the puzzle. A better bet is the little company with a solid link to a tech giant like

Cisco

(CSCO) - Get Report

,

Intel

(INTC) - Get Report

or

Microsoft

(MSFT) - Get Report

, on the assumption that a big brother will protect its investment with more capital -- or equipment orders or marketing partnerships -- if need be.

For these, go to an

EDGAR search engine, enter a big-company ticker, and search for 13-Ds, which a company has to file when it buys more than 5% of another. Or call up a recent big-company proxy and note the emerging company boards on which its execs sit. Then go through the emerging companies' recent press releases for news of investments, marketing alliances, etc. Here are some examples of what this kind of search will turn up:

Net2Phone

(NTOP)

is a leader in Internet telephony, i.e., the transmission of voice over the Internet. Its stock is down 60% in the past year, and it lost $73 million in that period. But

AT&T

(T) - Get Report

and

Yahoo!

(YHOO)

, among others, recently bought big pieces of it at much higher prices, giving it a cash balance of more than $200 million and some serious marketing partners.

Excite@Home

(ATHM) - Get Report

is big in cable Internet access, with more than 1 million subscribers, and recently bought

Excite

, a portal with more than 51 million registered users. The past year has been frightening, with a loss of $676 million (vs. revenue of $138 million) and a stock that's down 70%. But with half a billion dollars in cash on hand and deepening equity and operational links to cable giants AT&T,

Comcast

(CMCSK)

and

Cox Communications

(COX)

, there doesn't seem to be a lot of near-term business risk here.

Healtheon/WebMD

(HLTH)

connects doctors, insurance companies and patients over the Internet, with a goal of making the whole mess more efficient and cost effective. Revenue doubled to $102 million in 1999, but the net loss quintupled to $288 million and its stock is down 80% from its high. On the other hand,

News Corp.

(NWS) - Get Report

and Microsoft recently signed on for wide-ranging partnerships, including big capital infusions. As a result, Healtheon now has more than $1 billion of cash on hand and a more-or-less guaranteed revenue base.

EarthLink

(ELNK)

recently merged with

MindSpring

, to become the second-largest Internet service provider in the U.S. Its stock is down more than 60% in the past year. But in early May,

Sprint

(FON)

-- which already owned a big piece -- bought 26 million more shares, giving it a 26% stake. A few days later, Sprint named EarthLink as the exclusive provider of a suite of Internet applications for its new broadband service.

So does having a big brother guarantee these companies' success? Of course not. But it does up the odds that they'll get the chance to fully execute their business plans. And right now that's more than most of the world's emerging tech stocks can say.

As usual, this column just scratches the surface, so tell me what I've missed and I'll do a follow-up the next time around.

John Rubino, a former equity and bond analyst, is a frequent contributor to Individual Investor, Your Money and Consumers Digest. His first book, Main Street, Not Wall Street, was published by William Morrow in 1998. At time of publication, he had no position in any stocks mentioned. While Rubino cannot provide investment advice or recommendations, he invites your feedback at

rubinoja@yahoo.com.

As originally published, this story contained an error. Please see

Corrections and Clarifications.