Thanks for this post and i hope folk will reply so that we can find
solutions to this. I find ubuntu a bit of a pain with 6-month
releases. My solution is similar i guess to what you seem to do. I
have two external drives; one for working files and another for a
spare copy as i call it to distinguish between actual backup from a
backup app system. I do a backup i.e. just a copy each weekend. I use
Firefox with foxmarks - my bookmarks file is vast. Emails - i use
webmail to make use of googlemail's conversations idea and then
Thunderbird and the ImportExport utility to archive on CD once a
year.{Thunderbird offers so much in the way of addons that other email
client's are way behind IMHO}.

I keep a smallish hard drive on the PC as it only has the system files
all working docs are saved on remote hard drive. Actual backup apps
i've not liked... i much prefer just to copy a drive or folder. I do
all manually either first day of the week i.e. Sunday morning or first
w/e of the month.