Text message to my Cricket wireless internet account that said: "You've just been Selected to Win a 1000$ Best Buy Gift card! But only the 1st 1000 users that goto http://confirmhere.info and enter code 7777 will receive it!" No "stop" instructions.
I decided to check out the site. When it asked for the code I plugged in something different. That code *did* get verified (I have a feeling anything would have) and the page redirected to http://premiumreward.net/ where there was a big box asking for my email. There was also some legalese below that, including links to a "privacy policy" and to "terms and conditions," neither of which I clicked on. and there was a check box to confirm I was over 18 and a U.S. resident.
I didn't go any further but it looks to me like an email harvesting scheme. I was just going to reply with "stop" but since it didn't come with those instructions I'm suspicious that this isn't even "legitimate" spam so I'll just report it to the Do Not Call Registry.