So you're asking about how to store something along the
line of perlmonks' chatterbox messages? In that case, I
wouldn't even bother with writing something that transient
to disk. The amount of content would likely be small enough
to use shared memory for it, or, if that gets to be too much
of a problem, you could use an in-memory
filesystem (such as linux's tmpfs; I don't know if freebsd
has an equivalent) with either flat files or a temporary
database that gets created on server startup. If you go with
flat files, remember mbox and maildir: You'll get better
performance (especially on deletes) by chunking the messages
into multiple files (say 1/message or 1/minute of messages)
instead of using one big file for everything.