I was googling some of the concepts from this chapter to find some links to interactive websites or video clips, and I came across this nice little video on recombination. It doesn't go too into depth on the phenomena, but it does raise an interesting point about what happens during recombination.
After the two strands have crossed over, there is actually a point where the two chromosomes are disconnected from each other, so as to form two new ones, via either a vertical or horizontal cut. What's interesting to notes is that the chromosomes require the vertical connections to be severed in order to perform correct recombination, yet the video eludes to the phenomena of the horizontal connections being able to be severed, enabling even more elaborate chromosomes to be formed (though they aren't recombinant of the two genes, as the video explains). It would be interesting to see if this random phenomena does definitely occur (the video never definitively defined if it does of doesn't), and if it does, how common/random is it?