At the federal level, one innovative solution can be found in the Partnership for Sustainable Communities, a collaboration of the Department of Housing and Urban Development ( HUD), the Department of Transportation ( DOT), and the Environmental Protection Agency ( EPA).

FORBES: Smart Communities will Build Green Infrastructure

Every state has a Department of Transportation (DOT) with a State Traffic Commission (STC) that is responsible for setting speed limits on certain state-maintained roads.

FORBES: The High Price Of Speeding

The Environmental Protection Agency (EPA) and the Department of Transportation (DOT) have formally announced their joint proposal to set stronger fuel economy and greenhouse gas pollution standards for model year 2017-2025 passenger cars and light-duty trucks.

WHITEHOUSE: Energy and Environment Latest News | The White House

America's Department of Transportation (DoT), which has some antitrust powers, has not only given its blessing to the rise of alliances, but actually requires airlines to collude fully within each of their groupings, and to share costs and agree on prices.

ECONOMIST: Airline alliances

The organized protest over hidden airline fees is the latest salvo in the battle over enhanced protections for air travelers a battle that will loom increasingly large as the deadline for comments on the latest proposals from the Department of Transportation (DOT) approaches on Sept. 23.

MSN: Hidden fees have airline passengers in a frenzy

According to a December 2011 report from the US Department of Transportation (DOT), 77% of the 6, 002 drivers surveyed admitted to answering phone calls on all, some or most car trips and said that there are only a few situations (such as bad weather or bumper-to-bumper traffic) where they would refrain from talking on the phone.

BBC: Should cars be a mobile-free space?

Snow plows and crews from the Texas Department of Transportation were still working in the area, DOT spokeswoman Veronica Beyer said.

CNN: Texas interstates reopen after blizzard

Last year, disability-issue complaints filed by air travelers with the Department of Transportation jumped a hefty 18.3% (DOT doesn't break out wheelchair issues).

WSJ: Airports Battle Bogus Requests for Wheelchair Assistance