Originally Posted by
AquaDyne
And my carry-on, first in the overhead bin, ended up getting relocated by a later flier who decided to put his even bigger bag over my head (despite his seat being a few rows back).
Do not let anyone move your bag to a different bin without your permission, or you may have a hard time finding or getting it later.
If it is fragile (especially if it is not obvious that it is fragile), be prepared to assist later boarding passengers if they need to rearrange the bin to put stuff in more space efficiently.