Are you sick and tired of wondering why panels is taking so freaking long to render a page? Well, now you'll know exactly which panes are to blame!
Panels, Why so slow? will show you—and everyone—exactly else how many milliseconds each pane takes to render. So, you probably don't want to enable this on a real site… unless you want to brag about how much you've optimized things.
Sponsored by DoSomething.org! Thanks to Sam Boyer for help figuring out how to hijack the render pipeline.