Aww man, those adjustments are painful when you have to make them. They always end with me debating whether I really need to fix that typo or can I just live with it, then eventually giving up and grumbling while I try to come up with the best fix that causes the least amount of pear-shaped potential.
I second the losing a bit of the outside margin and just slipping the column over. But if you lose too much outside margin, you can also try to select the master page and then go to the edit page and adjust the margin (make sure you check the box that says adjust the flow or something similar), InDesign will shift everything for you without you having to fix wayward text boxes.
This is how I've made changes when I need to make a fix to my margins and for the most part (especially if the nudge is small), I think I might have one or two faults that need fixing.
POD printers tend to bind tight, so I like to add some extra wiggle room with my inside margin, more than their minimum requirement. Then if I need to keep my page count down, I'll drop the font size by half a point (usually not noticeable, depending on the typeface).