"March is a time of traditions," said Jim Cramer on his "RealMoney" radio show Monday, referring to the "March Madness" men's college basketball tournament and its many investment opportunities.

This year the tradition will be huge, with a Gallup poll showing that 41% of America's workers are college-ball fans and that the games will be broadcast online for free for the first time, Cramer said.

About $3.5 billion to $4 billion was wagered on March Madness games last year, and this year online betting is expected to reach far more people, he added.

Cramer said that big-screen TVs are his first play on the tournament, telling listeners to look into Matsushita Electric Industrial ( MC), whose brands include Panasonic, Technics and JVC.

He called it the most undervalued company in the hardware game, with the stock selling at $21 a share.

As for what's inside your television, he said Trident Microsystems ( TRID) makes the brains of the TV. But, he warned, the stock is up a buck. If it pulls back, then Cramer would think about buying Trident.

He also likes Corning ( GLW) because the company makes the glass for big-screen TVs. The stock has pulled back 8% from its high, he said, and he believes that it's going higher.

Plus, the company also makes the fiber that will be used to replace the existing copper-based trunk-line system so that phone companies can pipe TV-quality video into homes, he said. And Cramer believes that this cycle will kick in for the stock later this year.

Where you buy the TV provides another play, and that means Best Buy ( BBY), he said.

"This stock confounded Wall Street last September when it blew up ... and missed estimates," Cramer said. "That was your chance. That was the big sale."

The stock is down $1.50 from its high. Cramer said that for those who want to pick up some Best Buy, it's a good idea to buy a little now, let it come down a bit and then buy a little more.

As for a play on online broadcasting, he said to forget about Comcast ( CMCSA), Cablevision ( CVC) and Time Warner ( TWX).

Cramer said that the money is in the technology that allows viewers to watch the game online, and that stock is Akamai Technologies ( AKAM), which creates global delivery services for Internet content and streaming media.

Akamai creates the algorithms and mathematical formulas that enable Internet traffic to go faster, he said

F5 Networks ( FFIV), which seems to hit a new high every day, makes the traffic control systems for the Internet highway, but Cramer said the stock is up and that it's not his style to buy when a stock is moving higher.

As for the gambling that comes with major sporting events, Cramer said that Las Vegas Sands ( LVS) is his favorite casino because of its tremendous exposure to Las Vegas and Macau.

He also likes Penn National Gaming ( PENN) now that Illinois has given it an opportunity to expand.

What did you spend $2,000 on 20 years ago? Cramer asked listeners. If it was on Microsoft ( MSFT), then your investment would be worth about $800,000.

"I can't come up with any other form of revenue generation that brings this kind of return other than stocks," Cramer said.

"Bonds can't do it. ... Gold, which has been so hot, can't do it. It's back to where it was 20 years ago. Real estate has been hot for six years, but before that it wasn't doing much at all," he said.

And that's why he wants listeners to stay in the game. Moreover, he believes that he can help find the next Microsoft for those who want to augment their paychecks.

As for Microsoft, which he owns for his ActionAlerts PLUS charitable trust, Cramer was quick to point out that the stock has been dead in the water for years.

"But while it has done nothing, it has gotten cheaper vs. its earnings," he said, referring to the fact that Microsoft's stock price-to-earnings ratio has come down.

Cramer said that he is willing to pay twice the growth rate for any company that's not crooked and has trustworthy management, and that Microsoft is trading below twice its growth rate.

Plus, the company is shipping out its new operating system later in the year, and everyone will have to upgrade.

Video travels over fiber but not over copper, so if phone companies want to continue to roll out video services, Cramer said we'll see all the copper in our trunk system replaced by fiber.

And Cramer believes that a basket of companies will benefit from this switch from copper to fiber optics, including MRV Communications ( MRVC), JDSU ( JDSU), Conexant ( CNXT) and Finisar ( FNSR).

Many of you lost a fortune in these plays in 1999 and 2000, Cramer said, but the past is the past. It will be impossible to replace all that copper with fiber over the next 18 months without these companies.

In his "10 Commandments on Investing" segment, Cramer told listeners that "your first loss is your best loss."

By this he means that when things go wrong, sometimes it's best just to cut your losses. "You can't have one or two positions that drag your whole portfolio down," he said.

"When you see the market going against you, when you see things aren't working, it's okay to take a loss early," Cramer said. Plus, if you like the stock, you can sell it, take the loss and buy it back lower.

He said that if you've done your homework, like the company's fundamental story and bought it for investment purposes, a downturn could be an opportunity to buy more.

But if the stock was bought for a trade, the catalyst happened and the stock moved lower, Cramer said to get out early and take the loss.

Want more Cramer? Check out Jim's rules and commandments for investing from his latest book by clicking here.

Here's your chance to pick the stock you'd like me to feature on my radio show March 16:
D.R. Horton

REMEMBER to listen in on Thursday for my take on the stock that wins this poll!

At the time of publication, Cramer was long Microsoft and Sears Holdings.

James J. Cramer is a director and co-founder of TheStreet.com. He contributes daily market commentary for TheStreet.com's sites and serves as an adviser to the company's CEO. Outside contributing columnists for TheStreet.com and RealMoney.com, including Cramer, may, from time to time, write about stocks in which they have a position. In such cases, appropriate disclosure is made. To see his personal portfolio and find out what trades Cramer will make before he makes them, sign up for Action Alerts PLUS. While he cannot provide personalized investment advice or recommendations, he invites you to send comments on his column by clicking here. Listen to Cramer's RealMoney Radio show on your computer; just click here. Watch Cramer on "Mad Money" at 6 p.m. ET weeknights on CNBC. Click here to order Cramer's latest book, "Real Money: Sane Investing in an Insane World," click here to get his second book, "You Got Screwed!" and click here to order Cramer's autobiography, "Confessions of a Street Addict."

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