[anfractuosity]

One of my favourite talks I watched was "Low Cost Non-Invasive Biomedical Imaging - An Open Electrical Impedance Tomography Project"

https://media.ccc.de/v/34c3-8948-low_cost_non-invasive_biome...

As it presented an interesting technique I'd never heard of before, along with an implementation.

Also I thought the 'Breaking the x86 Instruction Set' talk was extremely clever - https://www.youtube.com/watch?v=KrksBdWcZgQ