They do not and probably never will. All they do is give your computer a virus, and most likely crash it. Although some look legit, don't fall for it. It's just some sleezy guy trying to get people to download his program he created to just hurt people's comps.

Actually let me be the one to correct everyone here. There is no such thing as a Microsoft Generator.exe.
But there is a such thing as a Microsoft Generator. It was designed by Microsoft for Xbox Live Devs. What it does is, creates a fake account with a fake credit card and all fake information. The credit card has no limit because it does not exist. They don't lose any money because Microsoft points are an imaginary item. They have no value and are useless for anything except Xbox Live. So you can create this account on your XDK if it's connected to live. What it does is use and Administrative Emulator that accesses the system and allows them to pretty much take whatever you wanna take. So you can just add say 50,000 point and 4 years to one account and have someone else download it on their console. There you go, you now know how to get unlimited points/live. Hope this helped. Have a nice day and obey the rules.