I already wrote a post talking about my experience with zsh here but I haven't really even mentioned byobu anywhere that I remember, except maybe on irc.
byobu is a wrapper for gnu screen or tmux, it really is something you have to try if you like to test new software. It can do many many things, and learning them all is a bit challenging at first because it is mainly managed using your keyboard's F keys and you need to learn them by heart. However you only need to know two basic keystrokes:
F2 opens a new window (similar to ctrl + a + c in screen/tmux)
F6 dettaches your session (similar to ctrl + a + d in screen/tmux)
Heed that these two keys are only the two basic commands. F3 and F4 move form one window to the other up and down. Want to learn more? I am sure you do...