I could really do with a portable instant messenger that can work without an internet connection over a Local Network.
Any support would be great because using internet based IM's isnt possible on the network at school because of tight restrictions.
Running a program is not a problem, and i have a WLM portable that runs but the firewall blocks its acess.
called Bonjour or Rendezvous. They're both the same protocol, just got renamed due to trademark issues or some such.
Anyway, Miranda, Trillian, and I think Pidgin support it, so you should just need to install the right plugins for it, define an account, and it will autodetect the other LAN users... client-side firewall permitting.
You can try Softros messenger for LAN http://messenger.softros.com
We have tried this one in our university. It doesn't use an internet connection, pretty handy tool, sits in tray and just work
I've used Tonic (from R2 Studios) with good success. It doesn't need a server and won't even try to go beyond the local network (unless you tell it to).
If I remember correctly it uses the Registry, and probably wouldn't work for more than a couple hundred people, but otherwise it seems well behaved.
A good option for more people would be Jabber, but someone would need to run it on their machine as a server. If the network administrators want to be in control, they could set up the server themselves.
MC
I know you said no internet connection but if your school is just blocking ports the messengers use and you can surf the web via a browser then you should be able to use Meebo unless they block that site.
Once you go portable...