There's always a huge amount of guests on this site. As I type this there are 10 logged in users and 37 guests... that's quite a lot. So why don't they just join... go on... join! I dares ya!
I suppose they could be computer programmes tying to get in to spam the site up! Fancy that... Needless posts without any particular meaning whatsoever. Shame on you.
"Jonny Tightlips... you're shot! - whered' they get you?" "I ain't sayin' nutin'." "But what'll I tell the Doc?!" "Tell'um to suck a lemon."
Or, it could be webbots and webspiders that crawl the 'net for different sites. A great example can be found here . Though we've got a bunch of members, the number of visitors is largely inflated due to the Yahoo Webcrawlers and such.