The vbulletin forum on unicyclist.com was created in 2000 or 2001, but the online community is older, originally newsgroups. Content from 1993 is still available on the forum.
Are some of you from this era, were active on the online unicyclist community prior to the 2000s and still active today?
I have very hazy memories of reading rec.sport.unicycling on Usenet in the early/mid '90s with tin and xrn on Unix workstations (SunOS and HP-UX). This was pretty much just out of curiosity that such a thing existed to the extent that it had a newsgroup – there were a lot of ‘strange’ newsgroups on Usenet 
and even seeing what sort of diverse things people got up to was enlightening in a pre-web world!
I certainly wasn’t active on it though, and didn’t have a unicycle until many years later, but it perhaps implanted a seed… (!)
I joined the e-mail list in 1993 or 94 and had some involvement in the creation of the newsgroup.
I’m not sure when I first got connected to the online group; at that time, it was an email mailing list, but later became a Usenet Newsgroup, started or administered by Beirne Konarski (spelling from memory; may be slightly different). He was based in northern Ohio. I believe the mailing list originated at Harvey Mudd college in Claremont, California, where there was an active student unicycle club.
Not sure when I first got connected to that, but it all of a sudden made it possible for any connected unicyclists to communicate in near-realtime, which was unheard of before that. We used to create unicycle competition rulebooks by sending paper mail back and forth and gaining consensus on what text to go with! Lots of late night trips to the mailbox on my unicycle in those days… 
The following information has been pieced together from memory, and some historic files I have saved on my pc.
In November 1992, Terry Jones from Santa Fe took the initiative to establish the usenet newsgroup rec.unicycles, but the proposal failed. An e-mail list was set up as an alternative on January 19, 1993. This was the first form of online group-wise information exchange on unicycling, AFAIK. I was never subscribed to that list.
In March 1995, another attempt was made to create a usenet newsgroup, this time under the name rec.sport.unicycling. The initiative was spearheaded by Ken Fuchs, and co-proposed by Beirne Konarski, Jimmy Brokaw, Seth Golub, Jack Halpern, Iain Hibbert, Peter Philip, John Foss, Danny Colyer, and Mark Schecter. This time the proposal was successful.
I joined this newsgroup late 1999 or early 2000. Usenet was (is?) primarily text-based, although it was somewhat possible to exchange image files.
In March 2001, Kevin Gilbertson, better known as Gilby, founded unicyclist.com and set up the V-Bulletin forum. For some years, there was two-way synchronisation (called mirroring) between the newsgroup and the forum. In the next few years, basically the whole community moved over to the forum, which was much more capable than the newsgroup, e.g. it had built-in photo and video posting options. I myself used the two side-by-side for some years, gradually phasing out my newsgroup presence.
To be fair and complete the development story, it must be added that since around 2015, this forum has lost a lot of traffic to various Facebook groups such as Unicycle Chat.
To specifically answer your question, in addition to the names stated above: while I wasn’t active pre-2000, many names of those who were can be found through this page: Unicycling statistics. On that page you can find user names by level of activity on the newsgroup for 2001 u/i 2005 (as well as some other mildly interesting stuff). The page is not being maintained anymore.
The whole community apart from you and me, from what I remember 
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I always preferred usenet to web forums.
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