I love to kick off the new trading week by taking a quick peek at companies that have just hiked their dividends. A company that's easing up on its pocketbook probably has improving fundamentals to back up that generosity.

Readers of the Income Investor newsletter service can appreciate that kind of thinking. So let's take a closer look at four of the companies that inched their payouts higher over the past week.

Let's start with ONEOK (NYSE:OKE). The natural-gas distributor's new quarterly dividend is $0.42 a share, 5% higher than its previous rate. The active Income Investor recommendation has rewarded its investors by increasing its disbursements seven times since January 2006.

Unum (NYSE:UNM) is another booster. The employee-benefits specialist is sweetening its resume by upgrading its quarterly distributions by 10% to $0.0825 a share. I guess there's a bigger market than I figured in this iffy economy for disability income protection insurance. Go figure.

A.O. Smith (NYSE:AOS) is also heating things up. The manufacturer of water-heating equipment is jacking up its payouts by 3%. Shareholders will now be receiving $0.195 a share every three months. This may seem like a cyclical business, but A.O. Smith has boosted its yield seven times over the past eight years.

Finally, we have Landstar System (NASDAQ:LSTR) hauling along nicely. The provider of transportation and logistics services is bumping up its quarterly dividend by 13% to $0.045. Landstar drove ahead with the move, even as it announced a sharp decline in both revenue and profitability. 

Some of these moves may not sound like big deals, but consider the companies going the other way. Cousins Properties (NYSE:CUZ), Value Line (NASDAQ:VALU), and First Citizens Banc Corp cut their payouts last week.

Subscribers to the Income Investor newsletter service can appreciate the companies sending more and more money to their investors. The newsletter singles out companies that are committed to growing their distributions with market-thumping results.

Want to see what's being recommended these days? Give Income Investor a shot with a 30-day trial subscription. Who knows? Maybe the next thing to get an increase will be your interest.

Longtime Fool contributor Rick Munarriz pays attention to yield signs. He does not own shares in any of the companies in this story. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. ONEOK is a Motley Fool Income Investor pick. Value Line is a Motley Fool Stock Advisor recommendation. Try any of our Foolish newsletter services free for 30 days. The Fool has a disclosure policy.