Seven Reasons to Be Bullish Now

4. Low-P/E oils and financials. There's only so low the market can go when 50% of the companies that make up the S&P 500 are trading at single-digit multiples of enterprise value over EBITDA. (Enterprise value equals market cap plus net debt and represents a fairer assessment of what a buyer has to pay to buy the whole company. And EBITDA is earnings before interest, taxes, depreciation and amortization.) For instance, Goldman SachsGS, the best investment bank ever, has a P/E of 9. Exxon MobilXOM, the mega oil company, trades at six times EBITDA. Heck, even recent IPO Blackstone trades at nine times EBITDA.

5. Global economy boom. Eastern Europe, India and almost every part of the third world are building and rebuilding their cities, flushing out their infrastructure and beginning to participate in the global economy. Let's not forget that 40% of the revenues of S&P 500 companies are foreign sales. Not to mention that many of the companies that are building out the global infrastructure -- in particular General ElectricGE and ABBABB -- trade on the U.S. markets.

6. China. This deserves its own category. No matter how you slice it -- increasing numbers of Internet users, increasing demand for oil, increasing demand for steel and cement, increasing demand for financial services -- companies doing business in China are going to boom over the next 20 years. Whether you like Baidu.comBIDU as an Internet play, Korean steel producer PoscoPKX as a Warren Buffett play or PetroChinaPTR as an oil company, China is a strong market. And that doesn't necessarily mean buying Asian stocks. Even plays like railroad company Burlington NorthernBNI, which ultimately ships commodities from the Midwest to California so they can be sent to China, benefit from the China boom.

7. Tech upgrade cycle. Every aspect of technology is going to go through an upgrade in the next two to five years, and not just corporations upgrading their computers to handle Microsoft'sMSFT Vista operating system -- although that will happen. Individuals will move from analog to digital TV -- Best BuyBBY likely will benefit -- and consumers will buy phones that can handle Web access much like the AppleAAPL iPhone, and there's the entire alternative-energy tech boom, of which chipmaker Applied MaterialsAMAT will be a prime beneficiary.