As for the MIB and MJ-12, I believe that they exist. Their descriptions (on websites other than Above Top Secret) don’t sound too extraordinary. (Above Top Secret implies that the MIB are actually extra terrestrials and the MJ-12 murdered president J. F. Kennedy.) Below are the links to the MIB and the MJ-12 sections. If you want to know about the Omega Agency and the Shadow Government, go to AboveTopSecret.com. I will not fill my site with absurd claims that I don't believe in myself. The links:
The MIB are the exact opposite of Will Smith and Tommy Lee Jones. They do persuade people not to discuss their alien or UFO sightings, but they don't use the stick with the red light. They threaten people. Their main goal is not to have anybody killed, but to stop people from reporting sightings. Therefore, they sometimes, although rarely, resort to violence and may actually kill someone. MIB are usually in groups of three. They wear extremely neat black suits, black ties, and white shirts and sunglasses. Almost all of them drive black Cadillac's that look as if they had just been bought. All of them are male. Their skin is reported to be pale-white. Their hair is black. They have an expressionless face and speak in a monotone voice with their thin lips that appear to have lipstick on them. They often show surprise and puzzlement at such common, everyday objects such as books, pens, and spoons.
Supposedly, the MJ-12's mission: Don't let the public know about aliens and stop the aliens from conquering earth. I must say, I do not believe Aliens are going to conquer us.
Now that you've finished laughing, you can continue reading. Although I believe that there may be aliens, I think that they probably did not make contact with our government. If they have superior technology, what do they get from sharing it with us? Also, if anyone found out about the MJ-12 for real, they would be murdered. If anyone stumbled across a piece of secret information, they would be eliminated. No owner of an Area 51 website was killed so far.