If you're claustrophobic you won't want to watch this entry for one of the coolest action camera videos we've seen.
This entry into our list shows some incredible breath holding skills by free divers Andrew Ryzebol and Geoff Coombs. Free diving is dangerous enough without cutting a hole through thick ice on a frozen lake and then hoping you can find your way back before your breath runs out! Yet that's exactly what happens here. No doubt some significant safety precautions were taken to ensure the divers safe return as much as possible, but it's an extremely impressive demonstration of what the human body is capable of.