Noticed this the other day in the Mann Lake catalog (there may be others elsewhere). Basically a handheld roller, like a paint roller, covered in stiff spikes that you can roll over a capped frame to open all the cells before extraction.
Just curious - has anyone tried this, and if so, how did they like it? We can be reasonably certain that it works, as it's my understanding that at least some automatic uncapping machines use similar rollers and they work just fine. But how well does it work? Pros/cons?