dreaming_shaman is Alex's "catchall" IC LJ, he posts for a variety of characters through it, but has an icon for Pete, which I'm guessing goes with any and all Pete-related posts.
jugglingmercury is Johanna's version of the above. I'll use the pic of Andrea with any posts from her (and a tag, too, but that's just me)
carlossi is presumably deyo's character, Jason Carlossi.
And the rest of us are all OOC-muns. :)