yea yes yes I had the same idea. I couldn't participate in the second half of the Jam it could be fun to list all the left over projects (let's say day 2 or day 3) and take them as a starting point of a new mini Jam.
I had also the Idea to organise a 6dev / 6day 6project Jam where every project have to be pushed from day1 to day6 by a different dev
Meaning no left over and no project taken more than once a day.
(Could be less than 6 days) a 4/4/4 Jam