To bounce between multiple IMAP accounts with mutt, I created two files to hold the per-account settings and bound a macro key to the index screen that rotates (hence the 'R') between accounts:

update 2010-04-11:
forgot to html encode the macros below, so the vim commands were hidden....

folder-hook work.com 'source ~/etc/mutt/work'
folder-hook personal.org 'source ~/etc/mutt/personal' 
set folder=imaps://me@personal.org/

set folder=imaps://me@work.com/
set spoolfile=imaps://me@work.com/
macro index R \
<change-folder>imaps://me@personal.org/<enter> \
'personal imap' 

 
set folder=imaps://me@personal.org/
set spoolfile=imaps://me@personal.org/
macro index R \
<change-folder>imaps://me@work.com/<enter> \
'work imap'