In the interests of privacy, it's considered extremely bad taste to post any email that someone may have sent, unless they explicitly give you permission to redistribute it. While the legal issues can be heavily debated, most everyone agrees that email should be treated as anything one would receive via normal snailmail, {The slang for the normal land and air postal service.} , with all of the assumed rights that are carried with it.
Test Messages
Many people, particularly new users, want to try out posting before actually taking part in discussions. Often the mechanics of getting messages out is the most difficult part of Usenet. To this end, many, many users find it necessary to post their tests to "normal" groups (for example, news.admin or comp.mail.misc). This is considered a major netiquette faux pas in the Usenet world. There are a number of groups available, called test groups, that exist solely for the purpose of trying out a news system, reader, or even new signature. They include
alt.test gnu.gnusenet.test misc.test
some of which will generate auto-magic replies to your posts to let you know they made it through. There are certain denizens of Usenet that frequent the test groups to help new users out. They respond to the posts, often including the article so the poster can see how it got to the person's site. Also, many regional hierarchies have test groups, like phl.test in Philadelphia.
By all means, experiment and test—-just do it in its proper place.
Famous People Appearing
Every once in a while, someone says that a celebrity is accessible through "The Net"; or, even more entertaining, an article is forged to appear to be coming from that celebrity. One example is Stephen Spielberg—-the rec.arts.movies readership was in an uproar for two weeks following a couple of posts supposedly made by Mr. Spielberg. (Some detective work revealed it to be a hoax.)
There are a few well-known people that are acquainted with Usenet and computers in general—-but the overwhelming majority are just normal people. One should act with skepticism whenever a notable personality is "seen" in a newsgroup.
Summaries