I'm wondering if there's a client or a solution to make Skype work? I don't need the voice or video chat. I just want to be able to text chat with my contacts on Skype.
Skype for linux should do it. i don't know if .deb for debian on website would work on rpi raspbian but you could try it out. if it doesn't it will give you an error. note that skype takes quite a bit of RAM.
If there's a solution that can tie in multiple chats together like say Trillian can for windows I'd love to hear about as I'm looking for a solution to MSN as well. Are there any plugins for this to Irssi?
yes there are plenty solutions liek that. i think only skype can be used with skype while for other services you have:
Kopete & KDE Telepathy (these two might be a bit heavy for rpi)
Gyache (for improved Yahoo compatibility)
aMSN - free Windows Live Messenger clone (btw i think MSN will stop working anyway as microsoft plans to move users to Skype)
Ekiga (opensource alternative to skype)
there are also command line tools like talk and similar.
i would start with Pidgin and work from there. note that plenty of plugins are available for it to enhance it.