Fools were out and about this past week in an investing world jam-packed with actions and ideas. Here are three articles you might find useful as you decide how to invest your money.

82 Reasons We Love Warren Buffett
 Berkshire Hathaway's (NYSE: BRK-B) Warren Buffett turned 82 this week, giving Fools an extra reason to celebrate his investing acumen. Fool analyst Anand Chokkavelu published 82 reasons to love the man known as the Oracle of Omaha. Here are just three of the reasons Anand gave:

  • His time frame for the long run consistently exceeds his life span.
  • Once branded a stingy miser (rightly or wrongly), Buffett has evolved (assuming it wasn't his intention from the start) into one of the most effective philanthropists I know. After growing his potential givings at a 20% compounded rate per year, he set a plan to give most of it away.
  • Here's a good place to point out that available-to-all company annual reports are the primary fuel in his learning machine. He reads them voraciously to compare and contrast companies and build his business knowledge base. You can find annual reports on your companies' websites (look for an investor relations department) and visit the SEC's EDGAR database to access companies' annual 10-K reports.

Read the article for Anand's full rundown, and use the comments section on that page to let your fellow Fools know what you love about Buffett.

3 Undeniable Trends Investors Can Profit From
 Fool analyst Travis Hoium presents some investing ideas for those looking to take advantage of changes in the world's population and its energy sources. In terms of food, there is an increase in the number of people and an increase in the quality and quantity of food that people expect and can afford.

"Investing in companies that make agriculture more productive with less land will take advantage of this macro trend," Travis wrote. There are several avenues to investigate. For instance, Monsanto works with seeds, PotashCorp and Mosaic work with fertilizer, and Deere (NYSE: DE) works with equipment, Travis noted.

Travis lauds Deere as important to agricultural productivity around the world. "Trading below 10 times trailing earnings and paying a 2.4% dividend yield are nice treats for investors," he wrote.

Investors could look to Seadrill (NYSE: SDRL) to profit from the shift to drilling for oil in deeper water. "Even though oil isn't reaching record highs, the dayrates explorers are willing to pay for an ultra-deepwater rig are reaching new records, showing the demand that exists in the industry," Travis wrote. In the second quarter, Seadrill's revenue rose 7% to $1.12 billion and operating profit grew 6% to $483 million, Travis wrote.

Read the article to learn more about these two trends and a third one that Travis thinks investors should keep an eye on.

A Simple Example of the Disruption 3-D Printing Could Cause
 The share prices of 3-D printing companies 3D Systems (NYSE: DDD) and Stratasys (Nasdaq: SSYS) have grown more than 100% over the past year, but it's not too late for investors to get in on the potential of the disruptive technology, Fool analyst Brian Stoffel wrote. In the 3-D printing process, a machine follows instructions to create an object by laying down successive layers of materials such as metal or rubber.

Both companies look expensive -- with price-to-earnings ratios around 70 -- but "with market caps less than $3 billion, there's still plenty of room to grow over the next decade," Brian wrote. If he had to choose between the two, Brian said he would go with Stratasys. "This is largely due to the company's historical focus on organic growth and catering to large-ticket customers -- though it has recently branched out with lower-end printers as well," he wrote.

Read the article for more on whether 3-D printing can help boost your portfolio.

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