So if you're working with a large project, and especially if you're trying to debug something in a loop, conditional breakpoints really come in handy. Today I had a problem where I was in a loop for who knows how long, and I had to keep checking if a variable matched something. It's easy to set a breakpoint to do this for you though.
Double click on the left side of the line to set a regular breakpoint. Then right-click it and select Breakpoint Properties... Here you can add a conditional statement. Note that you don't need the if(), only what would be inside the if condition. What I used was:
$info['function'] == 'theme_viewscarousel_view'
So whenever the variable contains this value it halts execution just like I expect. Lifesaver!
You can use any PHP functions as well.
strpos($template_file, 'slideshow') > 0