Browsing randomly on Google Scholar (as one does) I found an excellent article about social roles in electronic communities. It describes several types of personalities that can be found in online fora:
Celebrities – Prolific posters who spend a good deal of time contributing to the community. Celebrities define what the community is.
Ranters – Prolific posters that have only one or two issues.
Lurkers – Readers who rarely participate (if at all). Apparently, lurkers are the silent majority, happy to read but not to write. Some celebrities may turn lurkers after a while.
Trolls – Trolls write inflammatory messages to elicit a response and create problems for the community. They tend to have various sock-puppets.
Flamers – Aggressive posters.
Newbies – The interesting thing about newbies is not the newbie himself/herself, but the way in which the community reacts to newbies. Some communities accept newbies, while others are suspicious of them.
Speech Communities – Groups that share the understanding of specific terms.
Linkers – People who provide no text, only links.
I find this relevant to the law because I am interested in how virtual communities organise themselves. The article says that there is some correlation between what the elite thinks (the celebrities) and what is going to be considered accepted behaviour by the community as a whole. This would suggest a type of online aristocracy in which the rules are set by the ruling and visible elite, while the silent majority complies.