Indeed scam-ish.  The "travel provider" is Global Travel Group.  See the linked site for additional info.  These things make me laugh and furious at the same time.  Good try Global Travel Group...LAME!

http://www.ripoffreport.com/reports/0/341/RipOff0341911.htm

I also received the same mailing showing SWA and Dollar Rent A Car. On the flip side of the fake boarding pass 1 it lists the travel provider as Global Travel Group out of Scottsdale Arizona.  Here is the WEB site -  http://www.vacationtoursusa.com/GLOBAL_TRAVEL_AZ.htm.  I did not call due to as you can see you have to sit through a 90 minute presentation.  It does say that this is not "TimeShare" but what is the difference, they will hound you and pressure you to buy their product.  Please respond if this turns out to be a good deal!!

It is for a travel group - you have to attend their seminar and you receive the tickets no purcahse necessary

June/3/2008
Recieved Letter looking like goverment envelope (Form 2008) inside, You've won 2 round trip tickets on Southwest also with logos of southwest airlines & dollar rent a car. paper boarding pass inside it. I am sure it ids a gimmick. Not an official Southwest airline prize. No identification of who the compmany is that sent it. BEWARE

I received the same thing today as well.  Inside it said that I was awarded two round trip airline tickets to any major International Airport....It also had the Dollar Rent a Car logo as well as Southwest Airlines.  I called after hours to see if there was any recording to indicate what business it was from but it was generic voice mail message.

I received a letter from a mailing service on June 3, 2008 whose envelope was designed to look like a letter from the government. The letter inside stated that I had won a contest and needed to call 1-888-610-3690 to claim the prize. As far as I can tell there are NO markings anywhere on the letter or on the envelope that indicate who it is from, but I could have missed something. Only the postmark identifies anyone unique, but it just gives the general account the sender has with the Post Office.

Here is the postmark if you can look it up:
Permit #850
Daytona Beach, FL

What business uses it?