OK, I've found mods to change passwords & change email addresses, but I can't find a mod for changing username.

Can anyone point me in the right direction?

If the records are associated with usernames, it's not a good idea to change them.

I think it has been stated that it would be a very bad idea to change usernames, but I can't remember all the reasons why.

Unoffical DBMan FAQ
http://webmagic.hypermart.net/dbman/

I realize this might not be the safest procedure but here's
my dilemma: I have a lot of existing members that I'm now
putting in the database. I want to assign usernames and
passwords to each record. Once a member visits the site,
they should have the opportunity to change BOTH their
username and password to something THEY want. It seems to
me that if the basic program checks against duplicate
usernames a mod could do the same to prevent any possible
duplicates.

Does anyone know how I might go about allowing the visitor
to change their username?