i remember someone making that, linux loading virtualbox with xp, in xp they loaded windows virtual pc and in there loaded windows 3.11
perhaps you could put 98se instead of 3.11 and the load a old virtual pc and then load 3.11
that would mean 4 levels of inception

of course the limitation is how much resources virtual box can give to the first machine working as a container for the rest, if i remember correctly is 2 cores and 4 gbs of ram?